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Avaya Configuring IP Exterior Gateway Protocols (BGP and EGP) User's Manual

1. IP0006A Figure 1 1 An Internet Connecting Three Autonomous Systems The routers at the edges or borders of autonomous systems are called gateways These gateways use exterior gateway protocols to exchange reachability information and to route packets between routing domains This guide describes how to configure and use the Border Gateway Protocol BGP and the Exterior Gateway Protocol EGP You do not have to configure BGP to use EGP or EGP to use BGP 1 2 308628 14 00 Rev 00 Exterior Gateway Protocols BGP EGP Border Gateway Protocol BGP The Border Gateway Protocol BGP is an exterior gateway protocol that border routers use to exchange network reachability information with other BGP systems BGP routers form peer relationships with other BGP routers Using an entity called a BGP speaker BGP peers transmit and receive current routing information over a reliable transport layer connection making periodic updates unnecessary BGP can be used both within and between autonomous systems BGP peers exchange complete routing information only when they establish the peer connection Thereafter BGP peers exchange routing information in the form of routing updates An update includes a network number a list of autonomous systems that the routing information has passed through the AS path and other path attributes that describe the route to a set of destination networks When multiple paths are available BGP com
2. Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Static Routes The IP Static Routes window opens 4 Click on Add The IP Configuration window opens 5 Set the following parameters Destination IP Address Address Mask Cost Next Hop Addr Next Hop Mask Preference Unnumbered CCT Name Click on Help or see the parameter descriptions beginning on page A 51 6 Click on OK Site Manager returns you to the IP Static Routes window Defining a Static Default Route If IP receives a data packet with a destination address that it is unable to match in its routing table it looks for a default route that it can use to forward the packet To include a default route in the routing table create a static route with a destination address of 0 0 0 0 For the next hop address specify a router that can forward the packet to its destination 308628 14 00 Rev 00 4 13 Configuring IP Exterior Gateway Protocols BGP and EGP Defining a Static Black Hole for a Supernet A router that advertises an aggregate route by using a supernet address to represent multiple explicit routes must be able to discard packets that match the supernet address but that do not match any of the explicit routes For example consider a router that advertises an aggregate route
3. cceeeee C 6 Comparing Cisco and Nortel Networks BGP Operational Commands 0ceee C 8 Interpreting the Cisco and Nortel Networks BGP Operational Table cceee C 9 Comparing BGP Route Selection Processes ccccccccessseeceeeesneeeeeeesneeeeessntaeeeeeenaaes C 11 PRR Expression OV IIOIS cb csesentes ccc ataa a aaa C 12 Nortel Networks AS_ Path Pattern Matching Symbols c ccccseeeeeeseeeseeeeeeeeeeeesaes C 13 Index x 308628 14 00 Rev 00 Figures Figure 1 1 An Internet Connecting Three Autonomous Systems ccceeeeeeeeees 1 2 Figure 1 2 BGP Connecting Two Autonomous Systems Running OSPF 0 1 4 Foe T S TG AS cirian ee E EA Aa aari 1 7 Figure 6 1 Establishing and Confirming a Connection Between BGP Peers 6 4 Figure 6 2 BGP over an Unnumbered Point to Point Link R T ness 6 19 Figure 8 1 IBGP Single Route Reflector Topology cceceeeeeeeeeeeeeeeeeetseeeeeneeees 8 2 Figure 9 1 BGP OSPF Autonomous System sssssessessssssnssnrsssiesnrnrrnrensenraennennennnne 9 2 Figure 9 2 IBGP ECMP Route Balanites dcctwncunmncmeiianenaiimmainmunie 9 3 Figure 9 3 IBGP ECMP Traflit Load Balancing scissors sssvieiieusienvsnimraniaiiss 9 4 Pair Sa ECMP Stale Pe ae ss uinsicn se co daav etd crvuilecaaad en cedeadaarsedannus cedeinise nada 9 6 Figure 10 1 EGP Connection Between Two Autonomous Systems Running RIP 10 2 30862
4. Site Manager returns you to the Configuration Manager window Enabling Equal Cost Multipath Support By default IP stores the best next hop to a destination in the routing table If traffic arrives on an interface IP determines the best route to the destination and forwards all packets out the next hop interface IP equal cost multipath support ECMP is a load balancing feature that allows IP to distribute traffic over multiple up to five equal cost paths to the same destination IP supports three methods of distribution for equal cost routes e Round robin distribution IP forwards each packet to a different next hop until it reaches the end of the list of available next hops then it repeats the list Round robin distribution makes full use of available resources but may cause packets to be delivered out of order e Source destination hash distribution based on the source and destination address IP forwards all packets with a given source and destination address to the same next hop This method increases the chances that the packets will be delivered in order 308628 14 00 Rev 00 4 5 Configuring IP Exterior Gateway Protocols BGP and EGP e Destination hash distribution based on the destination address only IP forwards all packets with a given destination address to the same next hop By default in cases where IBGP uses the IP routing table to determine the next IP hop to an IBGP peer IBGP does
5. Multi Exit Discriminator Multi Exit Discriminator Value Origin Replace As Path Local Preference Override Local Preference Value Next Hop Atomic AS Pattern BGP Community to announce BGP Community attribute action BGP Community to match AS Prepend Click on Help or see the parameter descriptions beginning on page B 2 8 Click on Done You return to the Configuration Manager window 308628 14 00 Rev 00 7 23 Configuring IP Exterior Gateway Protocols BGP and EGP Configuring BGP 4 AS Pattern Matching Table 7 7 describes the special characters used in the Nortel Networks implementation of AS pattern matching Table 7 7 Characters in AS Path Pattern Matching Symbol or Operator Meaning lt Denotes the beginning of an AS SEQUENCE segment gt Denotes the end of an AS SEQUENCE segment Denotes the beginning of an AS SET segment Denotes the end of an AS SET segment lt seq gt set Denotes an AS path containing a sequence in the first segment and a set in the second segment A Denotes the following pattern occurs at the beginning of the AS path Denotes the preceding pattern occurs at the end of the AS path Denotes logical OR match this or that X Matches exactly the AS specified by X _X Matches the AS pattern beginning with X for example _99 matches 99 991 9934 X Matches the AS pattern ending with X for example
6. 99_ matches 99 199 23299 7 24 308628 14 00 Rev 00 Chapter 8 Configuring a Route Reflector To avoid the high cost of a full mesh topology to support IBGP speakers within a large AS you can configure a router to function as an IBGP route reflector An IBGP speaker that needs to communicate with other BGP speakers in the AS establishes a peer to peer RR client session with the IBGP route reflector You configure an IBGP speaker to be a route reflector or RR client and establish peer to peer connections between reflectors and clients as described under the following topics Topic Page Configuring a Single Route Reflector in an AS 8 1 Configuring a Route Reflector Cluster 8 4 Configuring Multiple RR Clusters in an AS 8 6 Configuring an RR Client 8 9 Note When you configure a session between two IBGP route reflectors or an RR and an RR client you must configure both ends of the session Otherwise events may occur that cause BGP to shut down the session Configuring a Single Route Reflector in an AS An IBGP route reflector RR is an IBGP speaker that has established a peer to peer session with an IBGP speaker defined as an RR client 308628 14 00 Rev 00 8 1 Configuring IP Exterior Gateway Protocols BGP and EGP A route reflector e Receives route advertisements from RR clients and other reflectors e Forwards best route advertisements to RR clients and o
7. Adjacent Host X 121 Address Configuration Manager gt Protocols gt IP gt Adjacent Hosts None Any valid IP address or X 121 address X 25 only Specifies the X 121 address of the adjacent host Set this parameter only if you configured X 25 as the data link protocol and if this is a PDN X 25 DDN X 25 or BFE X 25 connection This address is needed for those protocols that cannot perform address resolution Enter the appropriate X 121 address 1 3 6 1 4 1 18 3 5 3 2 1 6 1 9 Remote Party Sub Address Configuration Manager gt Protocols gt IP gt Adjacent Hosts None An SVC subaddress Specifies the subaddress used to establish an SVC to the adjacent host Supply a valid SVC subaddress 1 3 6 1 4 1 18 3 5 3 2 1 6 1 10 Remote Party Type of Number Configuration Manager gt Protocols gt IP gt Adjacent Hosts International International Unknown Specifies the type of number used to establish an SVC to the adjacent host Supply the required value 1 3 6 1 4 1 18 3 5 3 2 1 6 1 11 A 56 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Adjacent Host Type Configuration Manager gt Protocols gt IP gt Adjacent Hosts Default FRE 164 Default FRX 121 FRDLCI Specifies the type of adjacent host Supply a value 1 3 6 1 4 1 18 3 5 3 2 1 6 1
8. 308628 14 00 Rev 00 Configuring and Customizing BGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Route with MED parameter Click on Help or see the parameter description on page A 7 6 Click on OK Site Manager returns you to the Configuration Manager window Configuring and Enabling MD5 Authentication BGP 4 TCP MD5 authentication lets you configure BGP peers to ensure secure message interchange BGP 4 TCP MD5 message authentication provides the following features e A TCP MDS signature can exist for BGP peers e Authentication and secret keys are configurable on a per peer basis Peers configured with common secret keys can authenticate each other and exchange routing information e Configurations can concurrently have BGP peers with authentication enabled and authentication disabled e Keys can be stored as either clear text or encrypted and this storage mode can be set on a per peer basis 308628 14 00 Rev 00 5 21 Configuring IP Exterior Gateway Protocols BGP and EGP When BGP 4 TCP MD5 authentication is enabled a router computes an MD5 signature for each TCP packet based on the TCP packet and a per peer secret key The ro
9. Click on Help or see the parameter descriptions beginning on pages B 2 7 Click on OK Site Manager returns you to the BGP4 Announce Policy Filters window 308628 14 00 Rev 00 7 17 Configuring IP Exterior Gateway Protocols BGP and EGP Specifying Matching Criteria fora BGP Announce Policy You can use the BCC or Site Manager to specify matching criteria for a BGP announce policy Using the BCC Navigate to the policy specific prompt and enter match For example the following command invokes a match prompt for BGP announce policy pol_1 announce pol_1 bgp match match bgp announce pol_1l To specify a match enter lt match_criterion gt lt value gt match_criterion value is one of the criterion value pairs shown in Table 7 6 7 18 308628 14 00 Rev 00 Table 7 6 Configuring BGP Accept and Announce Policies BCC Match Criteria for BGP Announce Policies Criterion Values Function as pattern Empty string or any regular expression Allows as_path pattern matching Enter a valid regular expression to indicate an AS and its position in a path The policy applies to all routes whose AS path includes the AS in that position For example the expression 200 means that the policy applies to all routes whose as_path attribute contains AS 200 as the last AS in the path external source any default direct static rip ospf egp bgp Specifies one or mor
10. For example the following command sequence defines a peer to peer session between an RR client and a route reflector represented by addresses 2 2 2 2 and 2 2 2 3 ip bgp bgp peer local 2 2 2 2 remote 2 2 2 3 as 2 peer 2 2 2 2 2 2 2 3 peer mode none peer 2 2 2 2 2 2 2 3 8 10 308628 14 00 Rev 00 Using Site Manager Configuring a Route Reflector Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on Add 8 Set the following parameters e Peer Address Peer AS e Local Address Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 The BGP Peer Parameters window opens 9 Click on OK Site Manager returns you to the BGP Peer List window 10 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 8 11 Chapter 9 Configuring Route and Traffic Load Balancing IBGP route balancing and traffic load balancing are two techniques that allow an IBGP speaker to distribute routes to t
11. Weight Value 8 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 8 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 Enable Configuration Manager gt Protocols gt IP gt BGP gt Weights Enable Enable Disable Enables or disables a weight assignment for a particular AS Set to Disable to disable the weight assignment for this AS set to Enable if you previously disabled this weight assignment and now want to reenable it 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 2 BGP Event Message Parameters Parameter Path Default Options Function Instructions MIB Object ID Peer Local Remote Configuration Manager gt Protocols gt IP gt BGP gt BGP Debug 0 0 0 0 0 0 0 0 The IP addresses for the BGP local peer and remote peer Specifies the IP address of the BGP local peer and the remote peer To obtain event messages about all connections between all BGP peers accept the default value 0 0 0 0 0 0 0 0 Enter a specific pair of IP addresses to obtain event messages about connections between the peers with that IP address combination To limit the a
12. announce any list 1 3 6 1 4 1 18 3 5 3 2 6 10 1 33 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies BGP Community attribute action Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies As Is Remove Append Replace A list of BGP communities Specifies the action to be taken on the BGP communities attribute in updates matching this policy Use the default As Is if you want the BGP Communities attribute to remain unchanged Select Remove to remove all BGP Communities from an update Select Append to add to the update the communities that you have specified with the BGP Community to announce parameter Select Replace to replace the existing communities with the communities you have specified 1 3 6 1 4 1 18 3 5 3 2 6 10 1 34 BGP Communities to match Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of BGP communities Specifies one or more BGP communities This policy applies to all BGP advertisements that match the list Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means match any
13. 8 Set the following parameters Name Cutoff Threshold Reuse Threshold Reachable Decay Unreachable Decay Max HoldDown Memory Limit Click on Help or see the parameter descriptions beginning on page B 3 9 Click on OK You return to the Route Flap Dampening List window 10 Click on Done You return to the BGP4 Accept Policy Filters window 308628 14 00 Rev 00 5 35 Configuring IP Exterior Gateway Protocols BGP and EGP To apply a route flap dampening template to an existing BGP accept policy complete the following tasks Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Accept Policies The BGP4 Accept Policy Filters window opens 6 Click on the accept policy to which you want to apply route flap dampening 7 Set the following parameters BGP Route Flap Dampening BGP Route Flap Dampening Template Click on Help or see the parameter descriptions beginning on page B 18 8 Click on Done You return to the BGP4 Accept Policy Filters window 5 36 308628 14 00 Rev 00 Chapter 6 Establishing a Peer to Peer Session A BGP speaker forms a neighbor relationship by establishing a TCP connection to another BGP
14. B 10 B 14 Peer AS accept B 10 B 14 Peer List accept B 7 Precedence announce B 28 Received BGP Next Hop announce B 41 Received EGP Gateway announce B 38 Received on RIP Interface announce B 32 Received OSPF Tag announce B 35 Received OSPF Type announce B 34 Replace As Path announce B 50 Route Flap Dampening accept B 18 Route Flap Dampening Template accept B 19 Route Origin accept B 11 B 15 Route Preference accept B 6 Rule Precedence accept B 7 Specific Inter AS Metric announce B 45 Weight Class accept B 11 poll mode for EGP neighbors 10 13 Poll Mode parameter 10 13 A 26 Poll Timer parameter 10 14 A 27 Preference parameter 4 13 A 53 product support xx Proxy parameter A 34 publications hard copy xix Index 5 R Redirect parameter A 36 redundant connection command 5 10 Registration Refresh Interval parameter A 43 Remote Autonomous System IP Address parameter EGP 10 9 EGP neighbor 3 5 A 24 Remote Peer IP Address EGP neighbor 3 5 A 25 route echo enabling and disabling for BGP 6 16 6 17 Route Filter Support parameter A 49 route flap dampening 5 31 route echo command 6 16 6 17 router id command 5 4 S Slot Mask parameter IP interface A 40 SMDS Arp Request Address parameter A 38 SMDS Group Address parameter IP interface A 37 soloist configuring BGP as 5 14 starting EGP 3 4 IP 3 1 state command BGP 5 2 global IP
15. BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 8 308628 14 00 Rev 00 B 29 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Advertise Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of network identifiers Specifies network IDs to include in place of the network IDs listed in the route to be advertised Specify a non null value only if the announce Action parameter is Propagate The values you enter in the advertise list determine the action taken If you supply a list of network IDs these IDs are advertised instead of the actual IDs in the route If you use the default an empty list the actual IDs are advertised By default BGP 4 aggregates subnets into their natural network IDs If you supply a list that includes the encoding 255 255 255 255 255 255 255 255 the actual network IDs are advertised along with the other IDs in the advertise list This allows advertisement of an aggregate or default along with the actual network If the actual network is a subnet and the advertising protocol supports subnet advertisements the
16. Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of BGP communities Specifies one or more BGP communities This list identifies which communities are associated with this rule Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means accept any list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 24 BGP Community attribute action Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies As Is Remove Append Replace A list of BGP communities Specifies one or more BGP communities This policy applies to all BGP advertisements that match the list Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means match any list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 25 Route Flap Dampening Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Enable Enable Disable Enables or disables route flap dampening on this accept policy To enforce route flap dampening on the routes specified by this accept policy set this parameter to Enable otherwise accept the default Disable 1 3 6 1 4 1 18
17. Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt BGP gt Peers Enable Enable Disable Enables or disables a BGP peer relationship with the specified IP address Set this parameter to Disable if you want to temporarily disable this peer relationship rather than delete it Or set it to Enable if you previously disabled this peer relationship and now want to reenable it 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 2 Min BGP Version Configuration Manager gt Protocols gt IP gt BGP gt Peers 4 3 or 4 Specifies the minimum acceptable BGP version to run on this peer connection Specify BGP 3 or BGP 4 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 8 Max BGP Version Configuration Manager gt Protocols gt IP gt BGP gt Peers 4 3 or 4 Specifies the maximum acceptable BGP version to run on this peer connection Specify BGP 3 or BGP 4 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 9 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters External Advertisement Timer Configuration Manager gt Protocols gt IP gt BGP gt Peers 5 seconds 1 to 2 147 483 647
18. IP address mask Specifies the subnet mask of the next hop router continued 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Table 4 1 BCC Static Route Parameters continued Parameter Values Defaults Meaning Instructions cost 1 default to 12 Specifies the number of router hops a datagram can traverse before reaching the destination IP address The IP router uses the cost value when determining the best route for a datagram to follow If you have enabled ECMP on the router for information see Enabling Equal Cost Multipath Support on page 4 5 you can configure up to 12 equal cost static routes preference 1 default to 16 Specifies a weighted value from 1 to 16 with 16 being the most preferred that the IP router uses to select a route when its routing tables contain multiple routes to the same destination To configure a black hole static route enter the maximum preference value For example the following command line configures a static route to destination 3 2 4 5 255 255 0 0 with default values for static route parameters The next hop address is 2 2 2 4 and the cost is set to 4 hops ip static route address 3 2 4 5 mask 255 255 0 0 next hop address 2 2 2 4 static route 3 2 4 5 255 255 0 0 2 2 2 4 cost4 static route 3 2 4 5 255 255 0 0 2 2 2 4 308628 14 00 Rev 00 Configuring and Customizing IP for BGP
19. MAC MD5 MED MEK MSS MTU NLRI NPK NVRAM OSPF Address Resolution Protocol autonomous system asynchronous transfer mode Border Gateway Protocol Bootstrap Protocol classless interdomain routing data encryption standard data link connection identifier equal cost multipath Exterior Gateway Protocol Fiber Distributed Data Interface Interior Border Gateway Protocol Internet Control Message Protocol Interior Gateway Protocol Internet Protocol local area network media access control Message Discriminator 5 Multi Exit Discriminator message encryption key maximum segment size maximum transmission unit network layer reachability information Node Protection Key nonvolatile random access memory Open Shortest Path First xviii 308628 14 00 Rev 00 Preface PPP Point to Point Protocol RARP Reverse Address Resolution Protocol RFC request for comments RIF routing information field RIP Routing Information Protocol RR route reflector SMDS Switched Multimegabit Data Service SNMP Simple Network Management Protocol TCP Transmission Control Protocol TFTP Trivial File Transfer Protocol UDP User Datagram Protocol WAN wide area network Hard Copy Technical Manuals You can print selected technical manuals and release notes free directly from the Internet Go to support baynetworks com library tpubs Find the product for which you need documentation Then locate the specific category and model or version for
20. Specifies the minimum number of seconds allowed between BGP updates for this peer connection The external advertisement interval controls how often the IP routing table is examined for changes BGP update messages for routes that originate outside this AS will be issued no faster than the number of seconds you specify with this parameter Either accept the current value or enter a value greater than 0 seconds 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 11 Connect Retry Timer Configuration Manager gt Protocols gt IP gt BGP gt Peers 120 seconds 0 to 2 147 483 647 Specifies the maximum number of seconds allowed between TCP connection attempts for this peer connection Either accept the current value or set this parameter to some other value A value of 0 indicates that no active attempt to establish a BGP connection to the peer is to be done Incoming calls from the peers will be accepted 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 12 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Holdtime Configuration Manager gt Protocols gt IP gt BGP gt Peers 90 seconds 0 or any decimal number greater than 2 Specifies the holdtime that will be inserted into an open message Upon receipt of the peer s open message the lesser of the two holdtimes w
21. Table 7 6 Configuring BGP Accept and Announce Policies BCC Match Criteria for BGP Announce Policies continued Criterion Values Function network List of IP addresses Specifies which networks will match this policy Each identifier consists of a network number a mask and a flag to indicate whether the ID refers to a specific network or a range of networks Enter a specific encoding of 0 0 0 0 0 0 0 0 to match the default route Enter a range encoding of 0 0 0 0 0 0 0 0 to match any route Enter an empty list to match any route ospf router id List of IP addresses Specifies the IDs of one or more OSPF routers This policy applies to OSPF advertisements authored by a router on this list and applies only to OSPF sourced routes and if OSPF is included as a route source ospf tag List of OSPF ASE tag values Specifies tag values that could be present in an OSPF ASE advertisement This policy applies to OSPF ASE advertisements that contain tag values in this list and applies only to OSPF sourced ASE routes and if OSPF is included as a route source outbound interface rip gateway List of IP addresses List of IP addresses Specifies a list of outbound RIP interfaces If an interface appears in this list the policy applies to RIP advertisements sent via that interface Specifies the addresses of one or more routers that could send RIP updates to this router This p
22. agencies and subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause of DFARS 252 227 7013 for agencies of the Department of Defense or their successors whichever is applicable 6 Use of Software in the European Community This provision applies to all Software acquired for use within the European Community If Licensee uses the Software within a country in the European Community the Software Directive enacted by the Council of European Communities Directive dated 14 May 1991 will apply to the examination of the Software to facilitate interoperability Licensee agrees to notify Nortel Networks of any such intended examination of the Software and may procure support and assistance from Nortel Networks 7 Term and termination This license is effective until terminated however all of the restrictions with respect to Nortel Networks copyright in the Software and user manuals will cease being effective at the date of expiration of the Nortel Networks copyright those restrictions relating to use and disclosure of Nortel Networks confidential information shall continue in effect Licensee may terminate this license at any time The license will automatically terminate if Licensee fails to comply with any of the terms and conditions of the license Upon termination for any reason Licensee will immediately destroy or return to Nortel Networks the Software user manuals and all copies Nortel Networks is not liable to
23. all subnets disabled classless disabled max policies 32 route filters enabled rip max paths 1 ecmp method disabled isp mode disabled ospf max paths 1 icmp error limit 0 ip 4 2 308628 14 00 Rev 00 Configuring and Customizing IP for BGP Opening the Site Manager Window for IP Global Parameters Use the following Site Manager procedure to open the IP Global Parameters window which displays all IP global parameters and their current values Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Global The Edit IP Global Parameters window opens Disabling and Reenabling Global IP IP is enabled on the slot by default You can change the state of IP as required Using the BCC Navigate to the IP global prompt and enter state lt state gt state is one of the following enabled default disabled For example the following command disables IP on the router ip state disabled ip 308628 14 00 Rev 00 4 3 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Global The Edit IP Global Parameters window opens 4 Set the Enable parameter Clic
24. between two route reflectors represented by addresses 2 2 2 2 and 2 2 2 3 located in the same cluster in AS 2 bgp peer local 2 2 2 2 remote 2 2 2 3 as 2 peer 2 2 2 2 2 2 2 3 peer mode reflector internal peer 2 2 2 2 2 2 2 3 308628 14 00 Rev 00 8 5 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on Add 8 Set the following parameters Peer Address Peer AS Local Address Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 The BGP Peer Parameters window opens 9 Click on OK Site Manager returns you to the BGP Peer List window 10 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Configuring Multiple RR Clusters in an AS An AS can contain multiple IBGP route reflector clusters In an AS with multiple clusters Each cluster has a unique ID Within each cluster RR clients are connected to RRs in a tree topo
25. eliminate transit fragmentation and destination reassembly for datagrams destined for this interface and therefore decrease network load Select Enabled to enable the Reply MTU option on this interface select Disabled to disable the option on this interface 1 3 6 1 4 1 18 3 5 3 2 1 24 1 12 AMR Configuration Manager gt Protocols gt IP gt Interfaces Disabled Enabled Disabled Specifies whether this interface generates ICMP Internet Control Message Protocol address mask reply AMR messages in response to valid address mask request messages The interface generates ICMP address mask reply messages in compliance with the relevant sections of RFCs 950 and 1009 Select Enabled to enable ICMP address mask reply message generation on this interface Select Disabled to disable ICMP address mask reply message generation on this interface 1 3 6 1 4 1 18 3 5 3 2 1 24 1 13 A 32 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters ASB Configuration Manager gt Protocols gt IP gt Interfaces Disabled Enabled Disabled Specifies whether the IP router floods All Subnet Broadcast ASB datagrams it receives out this interface An ASB datagram has a destination address equal to the broadcast address for an entire network all subnets For example if a
26. routing table 5 9 supplying identifier for 5 4 BGP authentication configuring 5 23 BGP Detect Redundant Connections parameter A 5 Index 1 BGP Dynamic Policy Change Support parameter 5 13 A 6 BGP Enable parameter 5 3 A 2 BGP From Protocols parameter 5 8 A 4 BGP Identifier parameter 5 4 A 3 BGP Interval Timer parameter 5 9 A 4 BGP Intra AS parameter 5 6 A 3 BGP Local AS parameter 5 5 A 3 BGP path selection Cisco and Nortel methods C 11 BGP Soloist Slots parameter 5 15 A 6 BGP IGP Interaction Control BGP parameter A 9 BGP OSPF interaction 1 10 Border Gateway Protocol BGP 1 3 Broadcast Address parameter A 31 C circuitless IP interfaces 3 6 Cisco BGP path selection Nortel equivalent C 11 Cisco commands Nortel equivalents 5 26 C 1 Cisco regular expressions C 12 Classless Inter Domain Routing CIDR 1 4 command equivalents Nortel and Cisco C 1 command equivalents Nortel and Cisco 5 26 Confederation ID BGP parameter A 8 Confederation Peer BGP parameter A 9 confederations 1 10 configuring BGP 5 1 configuring BGP MD5 authentication 5 23 Connect Retry Timer parameter 6 5 A 13 conventions text xvi Cost parameter IP interface A 31 IP static route 4 13 A 52 customer support xx customizing BGP 5 1 Index 2 D Default TTL parameter A 46 deleting BGP 3 3 BGP 3 3 3 EGP 3 6 Destination IP Address parameter 4 13 A 51 Detect Redundant Connecti
27. 0 0 to match the default route Enter a range encoding of 0 0 0 0 0 0 0 0 to match any route Use the default empty list to match any route MIB Object ID EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 5 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 5 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 5 B 4 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID Routing Policies Action Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies EGP Accept BGP 3 BGP 4 Ignore Accept Ignore Specifies whether the protocol ignores a route that matches the policy or forwards the route to the routing table manager Specify Accept to consider the route for insertion in the routing table To drop the route specify Ignore EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 6 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 6 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 6 308628 14 00 Rev 00 B 5 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID Route Preference Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Configuration Manager gt Protocols
28. 00 Rev 00 2 1 Configuring IP Exterior Gateway Protocols BGP and EGP For example the following command configures an Ethernet interface on slot 2 connector 2 box ethernet slot 2 connector 2 ethernet 2 2 Step 2 Configuring an IP Interface To configure an IP interface on a physical interface navigate to the prompt for the physical interface and enter ip address lt address gt mask lt mask gt address and mask are a valid IP address and its associated mask expressed in dotted decimal notation For example the following command configures IP interface 2 2 2 2 255 0 0 0 on an Ethernet physical interface on slot 2 connector 2 ethernet 2 2 ip address 2 2 2 2 mask 255 0 0 0 ip 2 2 2 2 255 0 0 0 The IP interface is configured on the Ethernet interface with default values for all interface parameters When you configure an IP interface the BCC also configures IP globally on the router with default values for all IP global parameters You customize IP by modifying IP global and interface parameters as described in Chapter 4 Configuring and Customizing IP for BGP 2 2 308628 14 00 Rev 00 Starting BGP Services with the BCC Starting BGP To start BGP 1 Configure BGP on the router 2 Define a BGP peer to peer connection Step 1 Configuring Global BGP To configure BGP on the router navigate to the global IP prompt and enter bgp BGP is now running on the router with default values for all BG
29. 10 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Configuring a Route Reflector Cluster You can connect multiple route reflectors in a route reflector cluster Within a cluster IBGP route reflectors must be connected in a full mesh topology To configure a route reflector in a cluster you establish a peer to peer session with one or more reflectors in the same cluster You can do this with the BCC or Site Manager 8 4 308628 14 00 Rev 00 Configuring a Route Reflector Using the BCC To establish a peer to peer session with another route reflector in the same cluster navigate to the global BGP prompt and enter peer local lt ocal_reflector_address gt remote lt remote_reflector_address gt as lt as_number gt local_reflector_address is the IP address of an interface on the local route reflector remote_reflector_address is the IP address of an interface on the remote route reflector as_number is an integer identifying the AS in which remote reflector is located Because the reflector and the client are located in the same AS BGP recognizes that this is an IBGP session When the session specific prompt appears enter the following command to specify that the remote route reflector is an internal peer that is located in the same cluster peer mode reflector internal For example the following command sequence defines a peer to peer session
30. 12 GRE Connection Name Configuration Manager gt Protocols gt IP gt Adjacent Hosts None A GRE connection name Specifies the name of the remote GRE connection to which an adjacent host is configured Supply an ASCII string 1 3 6 1 4 1 18 3 5 3 2 1 6 1 13 308628 14 00 Rev 00 Appendix B Routing Policies Topic Page Accept Policies Common Accept Policy Parameters B 2 EGP Specific Accept Policy Parameters B 7 BGP 3 Specific Accept Policy Parameters B 9 BGP 4 Specific Accept Policy Parameters B 13 Announce Policies Common Announce Policy Parameters B 24 EGP Specific Announce Policy Parameters B 41 BGP 3 Specific Announce Policy Parameters B 43 BGP 4 Specific Announce Policy Parameters B 47 308628 14 00 Rev 00 B 1 Configuring IP Exterior Gateway Protocols BGP and EGP Common Accept Policy Parameters Parameter Enable Path Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Default Enable Options Enable Disable Function Enables or disables this policy Instructions Set to Disable to disable the policy MIB Object ID EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 2 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 2
31. 2 6 8 1 25 Origin Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies As Is As Is IGP EGP Incomplete Specifies an Origin attribute override The Origin attribute of a route matching this policy will be replaced with the indicated value To allow the existing Origin attribute use the default 1 3 6 1 4 1 18 3 5 3 2 6 8 1 26 AS Path Override Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies An empty list A list of AS numbers Specifies an AS path override Enter a non null value to override the AS path attribute of a route matching this policy Each element of the AS path is an AS number Valid only if the Action parameter is set to Propagate Use the default empty list to allow the existing AS path attribute to remain in the route 1 3 6 1 4 1 18 3 5 3 2 6 8 1 27 308628 14 00 Rev 00 B 45 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Next Hop Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Null An IP address Overrides the Next Hop path attribute with the IP address you specify To allow the existing Next Hop attribute use the default null value 1 3 6 1 4 1 18 3 5 3 2 6 8 1 28 B
32. 3 5 3 2 6 6 1 17 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 17 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 17 308628 14 00 Rev 00 B 37 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Received EGP Gateway Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the IP address of one or more EGP gateways This policy applies to EGP advertisements that use a gateway on this list as the next hop and applies only to EGP sourced routes and if EGP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to EGP advertisements with any gateway address EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 18 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 18 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 18 B 38 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies From BGP Peer Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Polic
33. 3 5 3 2 6 9 1 26 B 18 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Route Flap Dampening Template Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies default when the Route Flap Dampening parameter is set to Enable Name of a configured route flap dampening template Specifies the name of the configured route flap dampening template to apply to the routes specified by this accept policy Enter the name of a configured route flap dampening template or accept the default template 1 3 6 1 4 1 18 3 5 3 2 6 9 1 27 Multi Exit Discriminator Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Passthru Override Generate Delete Name of a configured route flap dampening template Indicates whether to accept a Multi Exit Discriminator value for a network matching this filter and if accepted what value to use This parameter is valid only if the value of the Action parameter is accept Enter the name of a configured route flap dampening template or accept the default template 1 3 6 1 4 1 18 3 5 3 2 6 9 1 27 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object
34. 5 5 Local Preference Calculation Method State Meaning enabled default BGP uses BayRS formulas for local preference calculation and best route selection disabled BGP does not perform local preference calculation Instead it assigns a value of 100 to the route and uses a modified formula for best route selection For example the following command disables BayRS BGP local preference calculation and route selection bgp local pref calculation disabled bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Local Pref Calculation parameter Click on Help or see the parameter description on page A 8 6 Click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 5 29 Configuring IP Exterior Gateway Protocols BGP and EGP Configuring BGP Message Logging Site Manager allows you to control the event messages that BGP sends to the log file by specifying e Local and remote addresses of a peer to peer session or sessions e Message severity level fault warning information trace debug or all levels e BGP message type open update notification or keepalive Use BGP message logging parameters to l
35. 7 19 Characters in AS Path Pattern Matching noseia oeni T obni 7 24 BGP EOMP Methode cinerosnidisrienisnin aA 9 4 ELGP ECNE NENOOS sonoran a i 9 8 Router Mode Determinator cicccicciscsccnnisocsnonmivenconniercctenneevesnnanmrecnanncery 10 3 Cisco to Nortel Networks BGP Translation ccceceesseeeseereeseteeeeeeees C 2 Cisco and Nortel Networks BGP Operational Commands 0006 C 8 Route Selection Process Comparison cccccceseseeceeeeeeeeeaeeeeeeeees C 11 Regular Expression SONG ec scabies sceirsntaauncinine uusudaan imdncumiiutanabenennn C 12 Nortel Networks AS_Path Pattern Matching Symbols ee ETS C 13 308628 14 00 Rev 00 xiii Preface Routers at the borders or edges of autonomous systems are called gateways These gateways use exterior gateway protocols to exchange reachability information with each other and route packets between routing domains This guide describes how to configure and use the IP Border Gateway Protocol BGP and the Exterior Gateway Protocol EGP You can use the Bay Command Console BCC or Site Manager to configure IP including BGP and EGP on a router In this guide you will find instructions for using both the BCC and Site Manager Before You Begin Before using this guide you must complete the following procedures For a new router e Install the router see the installation guide that came with your router e Connect the router to the network an
36. A 42 ARP Server ATM Address User Part parameter A 43 AS parameter 6 22 A 19 AS weights for BGP 6 21 ASB parameter A 33 ATM ARP Mode parameter A 42 authentication 1 11 configuring 5 23 autonomous system AS definition 1 1 best route selection Cisco and Nortel methods C 11 BGP 6 9 AS weight classes 6 21 AS weights 6 21 best route calculation 5 27 5 28 308628 14 00 Rev 00 Index configuring and customizing 5 1 configuring as a soloist 5 14 configuring for intra AS routing 5 6 deleting from the router 3 3 EBGP route and traffic load balancing 9 5 enabling and disabling 5 2 dynamic policy configuration 5 13 intra AS routing 5 6 multihop connections 5 12 redundant connections 5 10 route echo switch 6 16 6 17 frequency of Keepalive messages for 6 8 holddown time for 6 11 IBGP route and traffic load balancing 9 1 identifying the local autonomous system AS 5 5 interior BGP IBGP 1 6 interval for initiating a peer to peer connection 6 4 Local Preference Attribute 5 27 maximum update size for 6 15 message logging 5 30 minimum AS origination interval for 6 12 multihop connections 5 12 negotiating the version 6 6 overriding the local AS number 6 14 path attributes 1 9 peers configuring over unnumbered point to point link 6 19 peer to peer communication 6 1 redundant connections 5 10 route reflector 8 1 route server 1 7 setting timer for injecting external BGP routes into
37. BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 2 B 2 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID Routing Policies Name Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt BGP 4 gt Accept Policies None Any alphanumeric character string Identifies this accept policy Specify a user name for the policy EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 4 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 4 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 4 308628 14 00 Rev 00 B 3 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Networks Path Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Default An empty list Options A list of network identifiers Each entry consists of a network number a mask and a flag to indicate whether the ID refers to a specific network or a range of networks Function Specifies the networks to which this policy applies Instructions Enter a specific encoding of 0 0 0 0 0 0
38. BGP speakers should use the same method to determine local preference and to select the best routes Note For a comparison of the Nortel Networks BCC and Site Manager equivalents for Cisco router configuration commands see Appendix C Translating Cisco to Nortel Networks Equivalents 5 26 308628 14 00 Rev 00 Configuring and Customizing BGP If you are configuring BGP in a network that also includes routers from vendors other than Nortel Networks you can use the BCC or Site Manager to disable BayRS local preference calculation and route selection Instead BGP assigns a value of 100 to externally received routes and uses the rules listed in Table 5 4 on page 5 28 for best route selection Calculating BGP 4 Local Preference Values BGP 4 update messages contain a local preference value that an AS border router can assign to a route when advertising it to IBGP peers The calculation of the local preference attribute is specific to each implementation A higher value indicates that the route is more preferred The router uses the following equation to calculate a value for the local preference attribute local preference 8191 origin value AS path weight where origin value is O for routes with an origin path attribute of IGP or 4096 for other routes and AS path weight is a sum of weight values associated with AS numbers listed in the route s AS Path attribute These weight values can be configured and default
39. IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on Add The BGP Peer Parameters window opens 8 Set the following parameters Peer Address Peer AS Local Address e Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 9 Click on OK Site Manager returns you to the BGP Peer List window 10 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Initiating a Peer to Peer Session A BGP speaker initiates a peer to peer connection by periodically issuing an open message BGP speakers respond to connection requests by returning open messages In Figure 6 1 for example BGP speaker A sends an open message to BGP speaker B to request a connection BGP speaker B responds by sending an open message to BGP speaker A Open message A to B ia DP BGP BGP speaker A speaker B Open message B to A Keepalive message Ato B BGP speaker B speaker A Keepalive message B to A IP0022A Figure 6 1 Establishing and Confirming a Connection Between BGP Peers All BGP speakers respond to connection requests from other speakers By default BGP attempts to
40. Interface List Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies An empty list A list of IP addresses Specifies a list of outgoing interfaces If an interface appears on this list the policy applies to EGP advertisements sent via that interface Specify one or more IP addresses Use the default empty list to indicate that this policy applies to any outbound interface EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 23 EGP Metric Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies 0 0 or an export metric value Specifies an optional export metric to use when advertising a route that matches this policy Select the default to indicate that the routing table metric calculated for EGP is to be used This parameter is valid only if the Action parameter is set to Propagate EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 24 B 42 308628 14 00 Rev 00 Routing Policies BGP 3 Specific Announce Policy Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID External Route Source Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Any Direct Static RIP OSPF with Type 2 metric EGP BGP Any Specifies one or more external route source identifiers If you specify an external rou
41. Manager returns you to the Configuration Manager window Enabling and Disabling Black Hole Punching If BGP advertises aggregate routes you can configure BGP to submit each aggregate route to the routing table as a black hole If IP receives a packet that does not match any of the explicit subnet routes the black hole route causes it to discard the packet For more information about black hole routes see Defining a Static Black Hole for a Supernet on page 4 14 By default BGP does not submit a black hole route to the IP routing table for an aggregate route that it advertises to a BGP peer You can use the BCC or Site Manager to enable this feature You can also configure IP to return an ICMP destination unreachable message to the sender of a packet to an unknown destination 5 18 308628 14 00 Rev 00 Configuring and Customizing BGP Using the BCC Navigate to the BGP prompt and enter black hole punching lt action gt action is one of the values described in Table 5 3 Table 5 3 Black Hole Punching Parameter Settings Value Meaning disabled default Disables black hole punching drop Enables black hole punching IP drops packets for an unknown destination without returning an ICMP message to the sender reject Enables black hole punching IP drops packets for an unknown destination and returns an ICMP destination unreachable message to the sender For example the following
42. Nortel Networks will replace defective media at no charge if it is returned to Nortel Networks during the warranty period along with proof of the date of shipment This warranty does not apply if the media has been damaged as a result of accident misuse or abuse The Licensee assumes all responsibility for selection of the Software to achieve Licensee s intended results and for the installation use and results obtained from the Software Nortel Networks does not warrant a that the functions contained in the software will meet the Licensee s requirements b that the Software will operate in the hardware or software combinations that the Licensee may select c that the operation of the Software will be uninterrupted or error free or d that all defects in the operation of the Software will be corrected Nortel Networks is not obligated to remedy any Software defect that cannot be reproduced with the latest Software release These warranties do not apply to the Software if it has been i altered except by Nortel Networks or in accordance with its instructions ii used in conjunction with another vendor s product resulting in the defect or iii damaged by improper environment abuse misuse accident or negligence THE FOREGOING WARRANTIES AND LIMITATIONS ARE EXCLUSIVE REMEDIES AND ARE IN LIEU OF ALL OTHER WARRANTIES EXPRESS OR IMPLIED INCLUDING WITHOUT LIMITATION ANY WARRANTY OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE Licensee is
43. Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Received OSPF Tag Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of tag values Specifies tag values that could be present in an OSPF ASE advertisement This policy applies to OSPF ASE advertisements that contain tag values in this list and applies only to OSPF sourced ASE routes and if OSPF is included as a route source Specify one or more tag values Use the default empty list to indicate that this policy applies to OSPF ASEs with any tag value EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 15 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 15 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 15 308628 14 00 Rev 00 B 35 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID From EGP Peer Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters
44. Point LINK c cecceeeseeeeteeeeeeteees 6 19 Assigning Weight and Class Values to an AS ou ececceeseeeeeceeeeeeeeeeeeeeeeeaeeeseeeeseeaeeeeaaeeees 6 21 Chapter 7 Configuring BGP Accept and Announce Policies Defining a BGP Accept Policy ieee P E G meee cece ee sche ae Supplying Modification Values for a BGP Accept Policy c ccccceccssecesseeesseeeeees 7 6 Specifying Matching Criteria for a BGP Accept Policy c ccceeccsecceeseeeesteeeeeeeeees 7 8 Defining a BGP Amonee POY orrasan inna aia AE 7 11 Supplying Modification Values for a BGP Announce Policy s es 7 14 Specifying Matching Criteria for a BGP Announce Policy pies ere eee cil Configuring BGPA AS Pattern MalehiNg xcctccciase tices castccersseedeis casmesctdvesneedonetenseanteanaes 7 24 Chapter 8 Configuring a Route Reflector Configuring a Single Route Reflector in an AS o cccceeeeceeecceceeceeeeeeeeeaeeeeeeeeeeeaaeeeeeneeee 8 1 ooniiguring a Route Reflector GS irnos ivi keinr ain N A 8 4 Configuring Multiple RR Clusters in an AS iu batons PEE Dena sees prema 1 8 6 Conmigurind an RR LENU iiine irea aE AEE 8 9 viii 308628 14 00 Rev 00 Chapter 9 Configuring Route and Traffic Load Balancing Configuring IBGP for Route and Traffic Load Balancing cccecceseeeeeeseeessteeeseeees 9 1 Configuring EBGP for Route and Traffic Load Balancing ccccccssseeeeseeesteeeeeeees 9 5 Chapter 10 Customizing EGP Ser
45. Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP From Protocols parameter Click on Help or see the parameter description on page A 4 6 Click on OK Site Manager returns you to the Configuration Manager window 5 8 308628 14 00 Rev 00 Configuring and Customizing BGP Setting the Update Interval Timer BGP injects external BGP routes into the routing table The default minimum interval between route injections is 5 seconds You can use the BCC or Site Manager to specify the minimum number of seconds between route injections Using the BCC Navigate to the BGP prompt and enter inject time lt seconds gt seconds is the minimum interval between route injections For example the following command causes BGP to inject external BGP routes into the routing table with a minimum interval of 10 seconds bgp inject time 10 bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP Interval Timer parameter Click on Help or see the parameter description on page A 4 6 Click on OK Site Manager
46. a datagram can traverse before reaching the destination IP address The IP router uses the cost value when determining the best route for a datagram to follow e The IP address of the next hop router e The subnet mask of the next hop router e A weighted value from 1 to 16 with 16 being the most preferred that the IP router uses to choose a route when its routing tables contain multiple routes to the same destination e The local router circuit associated with the static route over an unnumbered interface IP supports multiple static routes to the same destination IP uses the best route to forward packets and treats the other routes as backup routes in case the chosen route becomes unusable or is no longer considered the best route You can also configure IP to support equal cost multipath ECMP routes for traffic load balancing If IP considers the ECMP routes to be the best routes IP uses them all in the way you specify in round robin fashion for example to forward data For information see Enabling Equal Cost Multipath Support on page 4 5 With ECMP enabled globally on the router you can configure up to 12 ECMP static routes 308628 14 00 Rev 00 4 9 Configuring IP Exterior Gateway Protocols BGP and EGP Note When you dynamically create a new static route for example 128 10 8 0 255 255 255 0 1 the router can generate the following error message in the router log file 2 04 16 98 09 44 24 096 W
47. a router can use a supernet address to advertise a single route called an aggregate route that represents all of the destinations This reduces the size of the routing tables used to store advertised IP routes BGP 4 supports classless interdomain routing BGP Concepts and Terminology BGP is an exterior gateway protocol designed to exchange network reachability information with other BGP systems in other autonomous systems or within the same autonomous system Figure 1 2 shows two autonomous systems ASI and AS2 Networks within AS1 and AS2 are connected by routers running an interior gateway protocol in this case OSPF The two ASs are connected by routers that run an exterior gateway protocol BGP in addition to OSPF AS1 AS2 BGP connection IP00025A Figure 1 2 BGP Connecting Two Autonomous Systems Running OSPF 1 4 308628 14 00 Rev 00 Exterior Gateway Protocols BGP EGP Nortel Networks supports BGP 3 and BGP 4 e BGP 3 assumes that each advertised network is a natural class network A B or C based on its high order bits BGP 3 cannot advertise subnets or supernets e BGP 4 has no concept of address classes Each network listed in the network layer reachability information NLRD portion of an update message contains a prefix length field which des
48. access Not Forwarding configures the IP router to act as an IP host it does not forward IP traffic but it still processes packets explicitly addressed to it In Not Forwarding mode only static routes and adjacent host routes are allowed No routing protocols are initiated Because the IP router does not forward IP traffic in Not Forwarding mode you must configure the router to bridge IP traffic not explicitly addressed to it You must configure the bridge for each circuit that conveys IP datagrams The bridge then forwards all IP datagrams that are not explicitly addressed to the router 1 3 6 1 4 1 18 3 5 3 2 1 1 4 A 44 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters ARP Forwarding Configuration Manager gt Protocols gt IP gt Global Forwarding Forwarding Not Forwarding Specifies how ARP should act in relation to IP s forwarding state Note that Forwarding means IP is in forwarding mode If this parameter is set to Forwarding then ARP packets are either consumed if destined for the router or dropped If this parameter is set to Not Forwarding ARP packets are consumed if destined for the router or bridged onto remaining ARP interfaces Always set this parameter the way you set the Forwarding parameter 1 3 6 1 4 1 18 3 5 3 1 1 3 Nonlocal ARP Sour
49. add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 Weight Value 4 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 4 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 A 20 308628 14 00 Rev 00 Site Manager Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Weight Value 5 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 5 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in
50. ae eee eer Teen a ai cmon gy sone tee ter ter A 24 EGF CNR Psi TENS coiii ceaceadigd annae Eai A 25 IP PaCS eaaa a ania Aaa A 28 IP Configuration Parameters TEAT N T AT Seea n A 28 IP interece Parameters sci ececesencdacdecumescctirantivccedemnivacieanedi cantuaivederemiidersmamtanrenes A 30 PGDI PARTE ES aa aA A 44 308628 14 00 Rev 00 ix Bide Routes Parameters usnisa A A 51 Adjacent Host Parameters AT PT PET T T an R A 54 Appendix B Routing Policies Common Accept Policy Parameters oi c isccecsstcsss eatin eetstieien nisi cnerieteeendetiicanlinnins B 2 BGP Speciic Accept Policy Parameters ciccicictntessccstaseesssctnceaionesamnedicndaiedsiednteranecames B 7 BGP 3 Specific Accept Policy Parameters sessirnir aaa B 9 BGP 4 Specific Accept Policy Parameters a Senate ree T arena on B 13 Common Announce Policy Parameters siirius iirrnasiinssinnnisauemi sinasina B 24 EGP Specific Announce Policy Parameters ccccccccssseeeeeeeeeeeeeeeeeeeeeeeeeeeaeeeeeeees B 41 BGP 3 Specific Announce Policy Parameters ccccccsceeseeeeeeeeeeeeneeeseeeeeeneeessaees B 43 BGP 4 Specific Announce Policy Parameters ccccccccesseeseceeeceeeeseeeeeeseeeeeeeneeeseaees B 47 Appendix C Translating Cisco to Nortel Networks Equivalents Configuration Command Equivalents sccicscstisccstectcadicies teouevsntincndioneepiocdtseaetandetedetieets C 1 Interpreting the Cisco to Nortel Networks BGP Translation Table
51. any BGP peer use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 11 Originating AS Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of autonomous system numbers Specifies one or more autonomous systems This policy applies to BGP advertisements that originate from the ASs on this list To indicate that the policy applies to BGP advertisements originating from any AS use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 12 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Route Origin Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Any Any IGP EGP IGP or EGP Incomplete Incomplete or IGP Incomplete or EGP Specifies which values of the BGP origin attribute apply to this policy Select the origin values you wish to accept for this policy 1 3 6 1 4 1 18 3 5 3 2 6 9 1 13 Aggregator AS List Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt BGP 4 gt Accept Policies An empty list A list of AS numbers Specifies one or more autonomous systems This policy applies to BGP advertisements that contain in their Aggregator p
52. are higher in the table Table C 3 Route Selection Process Comparison Cisco BGP Path Selection Nortel Networks BGP Besi Route Calculation for Equal Routes al 2 3 10 If the path specifies a next hop that is inaccessible drop the update Prefer the path with the largest weight If the weights are the same prefer the path with the largest local preference If the local preferences are the same prefer the path that was originated by BGP running on this router If no route was originated prefer the route that has the shortest AS_path If all paths have the same AS_ path length prefer the path with the lowest origin type where IGP is lower than EGP and EGP is lower than Incomplete If the origin codes are the same prefer the path with the lowest MED attribute If the paths have the same MED prefer the external path over the internal path If the paths are still the same prefer the path through the closest IGP neighbor Prefer the path with the lowest IP address as specified by the BGP router ID 1 2 3 10 Choose the route with the higher BGP 4 route preference Choose the route with the higher Local Preference attribute if the BGP Global parameter local pref calculation is DISABLED non default the LP of routes will be set to 100 unless a policy overrides this Choose the route with the shortest AS path Choose the route with the smallest ORIGIN IGP lt EGP lt
53. disabled BGP restarts all BGP connections There is no advantage to disabling dynamic policy configuration Disabling this parameter will significantly impact BGP protocol operation overhead and network stability You can use the following Site Manager procedure to disable and reenable dynamic policy configuration Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP Dynamic Policy Change Support parameter Click on Help or see the parameter description on page A 6 6 Click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 5 13 Configuring IP Exterior Gateway Protocols BGP and EGP Configuring BGP as a Soloist By default BGP runs as a soloist on a slot determined by the BGP soloist slot mask Nortel Networks recommends that the slot mask include only nonforwarding slots so that BGP operations route calculation for example occur on one slot while the other slots maintain maximum forwarding capability If the slot on which the soloist is running fails BGP runs on an eligible slot By default BGP considers all slots with IP interfaces to be eligible slots You can use the BCC or Site Manager to specify a slot
54. for the BGP soloist Using the BCC Navigate to the BGP prompt and enter slot mask lt s ot gt slotis one of the values listed in Table 5 2 Table 5 2 Slot Mask Parameter Values Value Meaning all slots default BGP runs on all slots BGP is not a soloist 1 to 14 BGP is a soloist running on the specified slot For example the following command causes BGP to run as a soloist on slot 5 bgp slot mask 5 bgp 5 14 308628 14 00 Rev 00 Using Site Manager Configuring and Customizing BGP Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens Set the BGP Soloist Slots parameter Click on Help or see the parameter description on page A 6 Click on OK Site Manager returns you to the Configuration Manager window Associating a Route Reflector with a Cluster ID In an AS with multiple clusters of route reflectors you assign a cluster ID to each cluster and associate each route reflector with a cluster For information about the IBGP route reflector see Chapter 8 Configuring a Route Reflector Disabling and Reenabling Route Aggregation By default BGP aggregates non BGP originated subnet routes to their corr
55. gt BGP Global 5 seconds 1 to 2 147 483 647 Specifies the minimum time interval in seconds between injections of external BGP routes into the IP routing table Accept the default or enter a nonzero value 1 3 6 1 4 1 18 3 5 3 2 5 1 1 10 A 4 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Detect Redundant Connections Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Specifies whether redundant BGP connections to the same router will be detected and disallowed If you want only one BGP connection to the same router to be maintained use the default If you want to allow redundant connections enter Disable Collision detection is based on router ID If two BGP peers have multiple physical connections and want to establish a BGP session across each physical connection you must disable this parameter The advantage of a configuration with multiple physical connections is redundancy The disadvantage is that such a configuration results in multiple copies of each route 1 3 6 1 4 1 18 3 5 3 2 5 1 1 16 Multi hop EBGP Connection Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Disable Enable Disable Specifies whether BGP allows multihop connections to an external BGP peer By default BGP en
56. gt IP gt Policy Filters gt BGP 3 gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies 1 1 to 16 Assigns a metric value the higher the number the greater the preference to a route that the protocol forwards to the routing table manager If confronted with multiple routes to the same destination the routing table manager may need to use this value to decide which route to insert Either accept the default value 1 or enter a new value Routes for all networks 0 0 0 0 0 0 0 0 should have the lowest preference and routes for the most specific networks longest address and mask should have the highest preference EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 7 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 7 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 7 B 6 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID Routing Policies Rule Precedence Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies 0 A metric value Assigns a metric value to this policy a policy with a higher value takes precedence over a policy with a lower value Use this value to specify the order of preceden
57. information see Chapter 6 Establishing a Peer to Peer Session When the session specific prompt appears enter the following command to specify that the remote client is an internal peer that is located in the same cluster peer mode reflector internal For example the following command sequence defines a peer to peer session between the route reflector represented by IP address 2 2 2 2 and an RR client represented by IP address 2 2 2 3 ip bgp bgp peer local 2 2 2 2 remote 2 2 2 3 as 2 peer 2 2 2 2 2 2 2 3 peer mode reflector internal peer 2 2 2 2 2 2 2 3 308628 14 00 Rev 00 8 3 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on Add 8 Set the following parameters Peer Address Peer AS Local Address Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 The BGP Peer Parameters window opens 9 Click on OK Site Manager returns you to the BGP Peer List window
58. is not adequate If this is the case then enter the appropriate IP broadcast address in dotted decimal notation 1 3 6 1 4 1 18 3 5 3 2 1 24 1 9 Cost Configuration Manager gt Protocols gt IP gt Interfaces 1 1 to the value of the RIP diameter maximum 127 Sets the cost of this interface The interface cost is added to routes learned on this interface through RIP and is specified in subsequent RIP packets transmitted out other interfaces Enter the interface cost value standard RIP implementation assigns a cost of 1 however keep in mind that increasing this value causes the upper bound set by the RIP Network Diameter parameter to be attained more rapidly 1 3 6 1 4 1 18 3 5 3 2 1 24 1 8 308628 14 00 Rev 00 A 31 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID MTU Discovery Configuration Manager gt Protocols gt IP gt Interfaces Disabled Enabled Disabled Specifies whether the Reply MTU option option 11 in RFC 1063 is enabled on this interface When the option is enabled this interface responds to Probe MTUs option 12 in RFC 1063 A probe MTU requests the minimum MTU maximum transmission unit of all networks an IP datagram must traverse from source to destination By enabling this interface to respond to probe MTUs you
59. list 1 3 6 1 4 1 18 3 5 3 2 6 10 1 35 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID As Prepend Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of autonomous systems Specifies one or more AS numbers to be added as a SEQUENCE to AS Path Supply an octet string containing AS numbers to be added as a SEQUENCE to AS Path 1 3 6 1 4 1 18 3 5 3 2 6 9 1 36 308628 14 00 Rev 00 Appendix C Translating Cisco to Nortel Networks Equivalents This appendix shows you how to translate Cisco commands and functions into their Nortel Networks equivalents Topic Page Configuration Command Equivalents C 1 Comparing Cisco and Nortel Networks BGP Operational Commands C 8 Comparing BGP Route Selection Processes C 11 Regular Expression Symbols C 12 Nortel Networks AS_Path Pattern Matching Symbols C 13 Configuration Command Equivalents Table C 1 lists the Nortel Networks BCC and Site Manager equivalents for Cisco router configuration commands In this table Bold text indicates variables that the user supplies The items in the list following the table describe the functions that the correspondingly numbered row configures 308628 14 00 Rev 00 C 1 Configuring IP Exterior Gateway Protocols BGP a
60. peer Specify one or more IP addresses Configure an empty list to indicate that this policy applies to BGP advertisements being sent to any peer 1 3 6 1 4 1 18 3 5 3 2 6 8 1 23 Inter AS Metric Selector Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies None None Specified Originating Indicates whether or not an inter AS metric is to be advertised for a network matching this policy and if advertised what value to use Select None to indicate that no metric is to be advertised Select Specified to indicate that the value you specify in the Specific Inter AS Metric parameter is to be used Select Originating to indicate that the metric from the originating protocol will be used This parameter is valid only if the Action parameter is set to Propagate 1 3 6 1 4 1 18 3 5 3 2 6 8 1 24 B 44 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Specific Inter AS Metric Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Null Null or an AS metric Specifies a value for the inter AS metric Supply a value and set the inter AS Metric Selector parameter to Specified BGP 3 1 3 6 1 4 1 18 3 5 3
61. relationship rather than delete it Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose EGP The EGP menu opens Choose Neighbors The IP Interface List for EGP window opens Click on the IP interface you want The parameter values for that interface appear in the window Set the Enable parameter Click on Help or see the parameter description on page A 26 Click on Apply and then click on Done Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 10 11 Configuring IP Exterior Gateway Protocols BGP and EGP Choosing the Acquisition Mode In an EGP neighbor relationship one router is the active neighbor and the other router is the passive neighbor The router in the active mode is the initiator By default EGP assumes that the remote router is the passive neighbor You can use Site Manager to identify the remote router as the active neighbor Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose EGP The EGP menu opens 4 Choose Neighbors The IP Interface List for EGP window opens 5 Click on the IP interface you want The p
62. responsible for the security of its own data and information and for maintaining adequate procedures apart from the Software to reconstruct lost or altered files data or programs 4 Limitation of liability INNO EVENT WILL NORTEL NETWORKS OR ITS LICENSORS BE LIABLE FOR ANY COST OF SUBSTITUTE PROCUREMENT SPECIAL INDIRECT INCIDENTAL OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES RESULTING FROM INACCURATE OR LOST DATA OR LOSS OF USE OR PROFITS ARISING OUT OF OR IN CONNECTION WITH THE PERFORMANCE OF THE SOFTWARE EVEN IF NORTEL NETWORKS HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH DAMAGES IN NO EVENT SHALL THE LIABILITY OF NORTEL NETWORKS RELATING TO THE SOFTWARE OR THIS AGREEMENT EXCEED THE PRICE PAID TO NORTEL NETWORKS FOR THE SOFTWARE LICENSE 308628 14 00 Rev 00 iii 5 Government Licensees This provision applies to all Software and documentation acquired directly or indirectly by or on behalf of the United States Government The Software and documentation are commercial products licensed on the open market at market prices and were developed entirely at private expense and without the use of any U S Government funds The license to the U S Government is granted only with restricted rights and use duplication or disclosure by the U S Government is subject to the restrictions set forth in subparagraph c 1 of the Commercial Computer Software Restricted Rights clause of FAR 52 227 19 and the limitations set out in this license for civilian
63. restrictions as set forth in subparagraph c 1 ii of the Rights in Technical Data and Computer Software clause at DFARS 252 227 7013 Notwithstanding any other license agreement that may pertain to or accompany the delivery of this computer software the rights of the United States Government regarding its use reproduction and disclosure are as set forth in the Commercial Computer Software Restricted Rights clause at FAR 52 227 19 Statement of Conditions In the interest of improving internal design operational function and or reliability Nortel Networks NA Inc reserves the right to make changes to the products described in this document without notice Nortel Networks NA Inc does not assume any liability that may occur due to the use or application of the product s or circuit layout s described herein Portions of the code in this software product may be Copyright 1988 Regents of the University of California All rights reserved Redistribution and use in source and binary forms of such portions are permitted provided that the above copyright notice and this paragraph are duplicated in all such forms and that any documentation advertising materials and other materials related to such distribution and use acknowledge that such portions of the software were developed by the University of California Berkeley The name of the University may not be used to endorse or promote products derived from such portions of the software withou
64. returns you to the Configuration Manager window 308628 14 00 Rev 00 5 9 Configuring IP Exterior Gateway Protocols BGP and EGP Allowing Redundant Connections By default BGP performs redundancy checking on peer to peer TCP sessions BGP can maintain only one TCP session with a remote BGP peer If the remote peer attempts to establish another session on another physical connection BGP rejects the session BGP uses a collision detection method based on the router ID to check for redundant sessions The advantage of a peer to peer configuration with multiple sessions on multiple physical connections is redundancy if one connection fails the peers can communicate over another link The disadvantage is that such a configuration results in multiple copies of each route You can use the BCC or Site Manager to disable redundancy checking to allow TCP sessions with the same remote peer on multiple physical connections You can also use the BCC to specify the maximum number of redundant routes that BGP allows By default BGP allows up to 255 redundant routes Using the BCC To disable or reenable redundancy checking navigate to the BGP prompt and enter redundant connection lt state gt state is one of the following enabled default disabled To specify the maximum number of redundant routes navigate to the BGP prompt and enter max redundant routes lt max_routes gt max_routes is the maximum number of re
65. state is one of the following enabled default disabled 308628 14 00 Rev 00 6 17 Configuring IP Exterior Gateway Protocols BGP and EGP For example the following command disables loop detection on peer to peer session 2 2 2 2 2 2 2 4 peer 2 2 2 2 2 2 2 4 detect as loop disabled peer 2 2 2 2 2 2 2 4 Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window Set the Loop Detection parameter Click on Help or see the parameter description on page A 16 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Specifying the Route Reflector Mode of the Remote Peer For complete information about configuring a route reflector see Chapter 8 Configuring a Route Reflector 6 18 308628 14 00 Rev 00 Establishing a Peer to Peer Session Configuring Peers over an Unnumbered Point to Point Link You cannot c
66. subnet is advertised EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 10 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 10 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 10 B 30 308628 14 00 Rev 00 Routing Policies Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID From RIP Gateway Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the addresses of one or more routers that could send RIP updates to this router This policy applies to RIP advertisements from routers on this list and applies only to RIP sourced routes and if RIP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to RIP updates from any router EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 11 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 11 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 11 308628 14 00 Rev 00 B 31 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Received on RIP Interface Configuration Manager gt Protocols gt
67. that you specify BGP reduces the penalty value by half BGP uses a half life decay algorithm to decrement the penalty value 308628 14 00 Rev 00 5 31 Configuring IP Exterior Gateway Protocols BGP and EGP e Maximum holddown time If the route remains suppressed after the number of minutes that you specify BGP unsuppresses it even if the penalty value exceeds the threshold This action does not change the penalty value e Memory limit If the status of the route remains unchanged either reachable or unreachable after the number of minutes that you specify BGP unsuppresses the route if it is suppressed and resets the penalty value and flap count to 0 BGP provides a default template You can also use the BCC or Site Manager to create a route flap dampening template and a BGP accept policy for route flap dampening Using the BCC To create a route flap dampening template navigate to the global BGP prompt and enter damping template name lt name gt name is a unique name identifying the template A template specific prompt appears For example the following command creates a route flap dampening template named steady bgp damping template name steady damping template steady To define the parameters of a template you created navigate to the template specific prompt and enter lt parameter gt lt value gt parameter value is one of the combinations described in Table 5 6 5 32 308628 14 00 Rev 00 C
68. the list of gateways on the common network the networks they can reach and associated distances Both active and passive neighbors can send routing update messages The active neighbor usually sends a routing update response after it sends a poll message The passive neighbor usually sends a routing update response in response to a poll message 10 4 308628 14 00 Rev 00 Customizing EGP Services EGP Implementation Notes This section provides you with some important guidelines to follow when you configure EGP If you do not follow these guidelines EGP will become disabled on the interfaces involved Autonomous system numbers must be from 1 to 65 535 Two autonomous systems connected by an EGP link must have different autonomous system numbers The remote IP address cannot be the same as any of the local IP interface addresses The remote IP address must be on the same subnet as one of the local IP interfaces EGP does not have any loop avoidance techniques avoid loop topologies otherwise you will have to configure EGP route filters to counter the redundancies An EGP configuration between two ASs each using a subnetted interface to a class A network results in a routing black hole RIP Version 1 aggregates the single subnet into the natural network but the gateway router does not have complete subnet information or a natural network route to match the one being advertised by RIP Version 1 This black hole is not a
69. the steps in the following table Site Manager Procedure You do this System responds 1 Inthe Select Protocols window select the The IP Configuration window opens following protocols IP EGP Then click on OK 2 Set the following parameters IP Address Subnet Mask Transmit Beast Addr UnNumbered Assoc Address Click on Help or see the parameter descriptions beginning on page A 28 3 Click on OK The EGP Configuration window opens 4 Set the following parameters Local Autonomous System ID decimal Remote Peer IP Address Gateway Mode Click on Help or see the parameter descriptions beginning on page A 24 5 Click on OK Site Manager enables EGP service and returns you to the Configuration Manager window 308628 14 00 Rev 00 3 5 Configuring IP Exterior Gateway Protocols BGP and EGP Deleting EGP from the Router You can delete EGP from all router circuits on which it is currently enabled To delete EGP complete the following steps Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose EGP The BGP menu opens 4 Choose Delete EGP Site Manager opens a window prompting Do you really want to delete EGP 5 Click on OK Site Manager removes EGP from all circuits on the router and returns you to the Conf
70. to 8 A steep penalty is applied to routes that are advertised with an origin attribute other than IGP that is EGP or incomplete For an OSPF internal route or a direct route the local preference attribute is set to local preference 8191 256 metric 255 where metric is the OSPF metric for an OSPF route or the configured cost for a direct route For a RIP route an EGP route an OSPF ASE route or a static route the local preference attribute is set to local preference 256 metric where metric is the RIP metric for a RIP route the EGP metric for an EGP route the OSPF metric for an OSPF ASE route or the configured cost for a static route Note that local preference values for OSPF internal routes and direct routes are higher than the local preference values calculated for BGP routes 308628 14 00 Rev 00 5 27 Configuring IP Exterior Gateway Protocols BGP and EGP Best Route Selection Table 5 4 BGP uses the rules in Table 5 4 as tie breakers to select the best BGP route This table lists the rules in the order in which they are evaluated Best Route Selection Rules Default Preference Tie Breaker Rules Calculated Preference Tie Breaker Rules il 2 3 NO Choose the route with the lower route weight Choose the route with the higher local preference attribute Choose the route with the lower multiexit discriminator MED attribute if both routes include this optional at
71. using the supernet address 192 32 0 0 255 255 248 The supernet address represents eight specific networks 192 32 0 0 to 192 32 7 0 After the aggregate route has been propagated the router receives network traffic for each of these specific destinations At some point the router loses connectivity to network 192 32 3 0 one of the networks in the supernet The router continues to forward traffic that matches destinations 0 0 to 2 0 and 4 0 to 7 0 However the router can no longer find a complete match in the routing table for the disconnected network 3 0 The router must drop all traffic destined for 192 32 3 0 To force the router to drop the packet for an unmatched destination you configure a special type of static route for a supernet called a black hole To do so e Enter the supernet address mask pair as the destination IP address and address mask e To create the black hole enter the black hole encoding 255 255 255 255 as the next hop address and the next hop mask 308628 14 00 Rev 00 Chapter 5 Configuring and Customizing BGP Configuring BGP Globally You configure and customize the Border Gateway Protocol BGP parameters as described under the following topics Topic Page Enabling and Disabling BGP 5 2 Supplying a BGP Identifier 5 4 Identifying the Local AS 55 Disabling and Reenabling IBGP Support S6 Specifying Route Ty
72. want to import IBGP routes into an OSPF domain or into a RIP domain BGP IGP interaction control is a bit map configuration Select the appropriate option If you specify a value of zero there is no BGP IGP interaction 1 3 6 1 4 1 18 3 5 3 2 5 1 1 30 308628 14 00 Rev 00 A 9 Configuring IP Exterior Gateway Protocols BGP and EGP BGP 3 Global Parameter Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt BGP gt BGP 3 Global Enable Enable Disable Globally enables or disables BGP 3 on all router interfaces Set to Disable if you want to disable BGP 3 for the entire router 1 3 6 1 4 1 18 3 5 3 2 5 2 1 2 BGP 4 Global Parameter Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt BGP gt BGP 4 Global Enable Enable Disable Globally enables or disables BGP 4 on all router interfaces Set to Disable if you want to disable BGP 4 for the entire router 1 3 6 1 4 1 18 3 5 3 2 5 3 1 2 BGP Peer Parameters Parameter Path Default Options Function Instructions MIB Object ID Peer Address Configuration Manager gt Protocols gt IP gt BGP gt Peers None Any IP address Specifies the IP address of the interface on the remote side of this BGP peer connection Enter the IP address in dotted decimal notation If the peer is
73. within the specified timeout period Select Off to disable timeout on this interface the IP router does not time out address resolution cache entries Select one of the other options to enable timeout with a timeout interval equal to the value you select for example 120 seconds the IP router removes address resolution cache entries that have not been accessed within the specified number of seconds Once an entry is removed the IP router must use ARP to reacquire the physical level address 1 3 6 1 4 1 18 3 5 3 2 1 24 1 17 A 34 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Upd Xsum On Configuration Manager gt Protocols gt IP gt Interfaces Enabled Enabled Disabled Specifies whether UDP checksum processing is enabled on this interface Select Enabled to enable UDP checksum processing for the interface all outgoing and incoming UDP datagrams are subject to checksumming You should select Enabled in virtually all instances Select Disabled to disable UDP checksum processing and provide backward compatibility with UNIX BSD 4 1 1 3 6 1 4 1 18 3 5 3 2 1 24 1 18 MAC Address Configuration Manager gt Protocols gt IP gt Interfaces None 0 a user specified MAC address if the interface is on an SMDS circuit the entire E 164 address for
74. 1 1 4 255 255 0 0 198 2 1 1 back ip static route 201 1 1 4 30 192 32 28 51 static route 201 1 1 4 255 255 0 0 192 32 28 51 back ip bgp bgp router id 201 1 1 1 bgp local as 11 bgp multi hop enabled bgp peer 201 1 1 1 201 1 1 4 as 12 peer 201 1 1 1 201 1 1 4 ebgp ecmp method route balance peer 201 1 1 1 201 1 1 4 back bgp 9 8 308628 14 00 Rev 00 Configuring Route and Traffic Load Balancing Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters 8 Set the Peer EBGP ECMP parameter Click on Help or see the parameter descriptions beginning on page A 17 The parameters for that peer appear in the window 9 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 9 9 Chapter 10 Customizing EGP Services This chapter explains how to configure the Exterior Gateway Protocol EGP Topic Page EGP Concepts a
75. 1 to 65 535 Identifies the autonomous system to which this BGP router belongs Enter a value from 1 to 65 535 1 3 6 1 4 1 18 3 5 3 2 5 1 1 5 BGP Global Parameters Parameter Path Default Options Function Instructions MIB Object ID BGP Enable Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Globally enables or disables BGP on all router interfaces Set to Disable if you want to disable BGP for the entire router Set to Enable if you previously disabled BGP and now want to reenable it 1 3 6 1 4 1 18 3 5 3 2 5 1 1 2 A 2 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters BGP Identifier Configuration Manager gt Protocols gt IP gt BGP gt BGP Global None An IP address of an IP interface on this router Identifies the BGP router There is no default for this parameter You must use an IP address of one of the router s IP interfaces Either accept the current BGP identifier or enter a new IP address The BGP identifier must be one of the router s IP interfaces If both BGP and OSPF are running on the router then the OSPF router ID must be equivalent to one of the configured IP interfaces 1 3 6 1 4 1 18 3 5
76. 2 Mask Configuration Manager gt Protocols gt IP gt Interfaces You specified the subnet mask when you added IP to the circuit Depend on the class of the network to which the interface connects Specifies the network and subnetwork portion of the 32 bit IP address Enter the subnet mask in dotted decimal notation 1 3 6 1 4 1 18 3 5 3 2 1 24 1 6 A 30 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Broadcast Address Configuration Manager gt Protocols gt IP gt Interfaces You specified the broadcast address when you added IP to the circuit 0 0 0 0 or any IP address Specifies the broadcast address that the IP router uses to broadcast packets Accepting 0 0 0 0 for the broadcast address specifies that the IP router will use a broadcast address with a host portion of all 1s Accepting 0 0 0 0 does not configure the router to use the address 0 0 0 0 to broadcast packets For example if you have set the IP address to 123 1 1 1 and the subnet mask to 255 255 255 0 accepting the default value 0 0 0 0 configures the IP router to use the address 123 1 1 255 to broadcast packets For the explicit broadcast address of all 1s enter 255 255 255 255 for this parameter Accept the default 0 0 0 0 unless the calculated broadcast address host portion of all 1s
77. 2 6 10 1 9 Outbound Peer AS Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of AS numbers Specifies a list of autonomous system numbers If an AS number is included in this list this policy applies to BGP advertisements being sent to BGP peers in that AS Specify one or more AS numbers Configure an empty list to indicate that this policy applies to BGP advertisements going to peers in any AS 1 3 6 1 4 1 18 3 5 3 2 6 10 1 22 308628 14 00 Rev 00 B 47 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Outbound Peers Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the IP address of one or more BGP peers If a BGP peer is included in this list this policy applies to BGP advertisements being sent to that peer Specify one or more IP addresses Configure an empty list to indicate that this policy applies to BGP advertisements being sent to any peer 1 3 6 1 4 1 18 3 5 3 2 6 10 1 23 Multi Exit Discriminator Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies None None Specified Originating Indicates whether or not a Multi Ex
78. 3 2 5 1 1 4 BGP Local AS Configuration Manager gt Protocols gt IP gt BGP gt BGP Global The current BGP Local AS value 1 to 65 535 Identifies the autonomous system to which this BGP router belongs Either accept the current BGP Local AS value or enter a new value for this parameter 1 3 6 1 4 1 18 3 5 3 2 5 1 1 5 BGP Intra AS Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Specifies whether BGP will perform intra AS IBGP routing Transit ASs should use intra AS routing Stub or multihomed ASs usually do not use IBGP intra AS routing 1 3 6 1 4 1 18 3 5 3 2 5 1 1 8 308628 14 00 Rev 00 A 3 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID BGP From Protocols Configuration Manager gt Protocols gt IP gt BGP gt BGP Global BGP BGP All Controls if intra AS routing is enabled the types of routes that BGP advertises in any IBGP sessions Select BGP to propagate only advertised routes learned from external BGP peers Select All to propagate routes learned from all route sources excluding IBGP and OSPF interarea and intra area routes which are never advertised with IBGP 1 3 6 1 4 1 18 3 5 3 2 5 1 1 9 BGP Interval Timer Configuration Manager gt Protocols gt IP gt BGP
79. 3 gt to all outgoing updates as specified by Cisco route map and Nortel Networks policy name setASPath Note If on Nortel Networks one uses as path instead of as path prepend the AS Path is replaced instead of appended to Announce advertisement of network 192 10 20 0 mask 255 255 255 0 to peer IP address 1 1 1 1 setting multi exit discriminator MED to 100 as specified by Cisco route map and Nortel Networks policy name AdvertiseMap In addition advertise any other networks with MED set to 50 Nortel Networks definition requires 2 separate announce policies with the more specific network advertised given the higher rule precedence C 6 308628 14 00 Rev 00 10 11 12 13 14 15 16 17 18 Translating Cisco to Nortel Networks Equivalents Accept incoming advertisements from peer 1 1 1 1 of AS Path that contain either exactly AS 1000 or 5000 as specified by Cisco as path access list 5 and Nortel Networks policy name IncomingRoutes Announce advertisements to peer 1 1 1 1 if the update includes an AS Path that matches lt 350 400 gt and deny updates of AS Path that contain lt 350 400 500 gt as specified by Cisco as path access list 5 and Nortel Networks policy names DenyAS and AllowAS Create a peer group named MyPeers with the following elements peer router AS is 333 advertise networks as specified by route map AdvertiseMap and accept incoming networks as specified by FilterMap Assign peer ro
80. 4 3 static black hole routes configuring A 51 A 52 definition 4 14 5 18 static routes definition 4 9 Subnet Mask parameter BGP 3 2 EGP 3 5 IP configuration A 29 supernet defining black hole for 4 14 5 18 support Nortel Networks xx Index 6 T Tcp Authentication BGP parameter A 17 Tcp Md5 Key BGP parameter A 19 Tcp Md5 Key Storage BGP parameter A 18 technical publications xix technical support xx text conventions xvi TR Endstation ARP Type parameter A 43 TR Endstation parameter A 36 Transmit Beast Addr parameter BGP 3 2 EGP 3 5 IP configuration A 29 U Udp Xsum On parameter A 35 UnNumbered Assoc Address parameter BGP 3 2 EGP 3 5 IP configuration A 30 Unnumbered Associated Alternate parameter A 42 Unnumbered CCT Name parameter 4 13 A 53 unnumbered interface definition 3 7 update size maximum for BGP 6 15 WwW Weight Value parameter 6 22 A 19 Z Zero Subnet Enable parameter A 47 308628 14 00 Rev 00
81. 4002 4003 and 4004 This router s confederation ID is 4001 It has a peer 1 2 3 4 within its routing confederation domain and another peer 3 4 5 6 outside 308628 14 00 Rev 00 C 7 Configuring IP Exterior Gateway Protocols BGP and EGP 19 Enables MD5 authentication on the TCP connection between the two BGP peers 132 245 10 1 and 132 245 10 2 In this example the MD5 key is bla4u00 2nkq Comparing Cisco and Nortel Networks BGP Operational Commands Table C 2 compares the corresponding Cisco and Nortel Networks BCC operational commands The itemized list following this table describes the function of the commands in the corresponding row of this table Table C 2 Cisco and Nortel Networks BGP Operational Commands Item Cisco Nortel Networks BCC 1 no synchronization default behavior 2 route reflector route reflector 3 bgp dampening Bgp dampening 4 confederation confederation 5 not supported collision detection BGP Monitoring Commands Item Cisco Nortel Networks BCC 6 show ip bgp show bgp routes 7 show ip bgp neighbors show bgp peers 8 show ip bgp neighbors show bgp timers 9 show ip bgp neighbors show bgp routes N 10 show ip bgp neighbors 1 1 1 2 show bgp routes p1 1 1 2 11 show ip bgp regexp 123 456 show bgp routes R 123 456 13 clear ip bgp neighbor ip address ip bgp peer local ip neighbor ip state disabled state enabled 14 debug ip bgp updat
82. 8 14 00 Rev 00 xi Table 1 1 Table 1 2 Table 4 1 Table 5 1 Table 5 2 Table 5 3 Table 5 4 Table 5 5 Table 5 6 Table 7 1 Table 7 2 Table 7 3 Table 7 4 Table 7 5 Table 7 6 Table 7 7 Table 9 1 Table 9 2 Table 10 1 Table C 1 Table C 2 Table C 3 Table C 4 Table C 5 Tables BGP 3 Path ANDU sistant chien aneai dai ae aaNeNite 1 9 BGP 4 Optional Path AttribUtES sss cutis sesicisieecasteendiesinenunenenr 1 9 BCC Static Roue ParaineletS sicciecscctsascciscctntesdocesasncdacenepiatedanuendee tonnes 4 11 Route Types for BGP Advertisement c ccceseeeeeeeeeeteeeeeeeeseteeteeeee DOT Slot Mask Parameter Values ionnta ikea eheaais airna oeieo n D 14 Black Hole Punching Parameter Settings cccccsseeeeeeeeeseeeeeeneeees 5 19 Best Route Selection RUES sasriionseriiiiraeiiooisineid nenaad niaai 5 28 Local Preference Calculation Method cccesceceeeeeeeeeeeeeeeeeeeeeeeenee 5 29 Route Flap Dampening Template Parameters s es 5 33 BCC Definition Parameters for BGP Accept Policies c ceeeeeeee 7 4 BCC Modification Parameters for BGP Accept Policies eeeee 7 6 BCC Matching Parameters for BGP Accept Policies sesen 7 9 BCC Definition Parameters for BGP Announce Policies PE 7 12 BCC BGP Announce Policy Parameter Overrides cccccsseeeeeenees 7 14 BCC Match Criteria for BGP Announce Policies ccccceseeeeeneees
83. 8 3 5 3 2 6 7 1 13 BGP 3 Route Preference Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies 1 1 to 16 Specifies a value that is used to compare a route that matches this policy with other BGP 3 routes that match the policy The larger the value the greater the preference To specify maximum preference enter 16 This parameter is valid only if the Action parameter is set to Accept 1 3 6 1 4 1 18 3 5 3 2 6 7 1 14 Weight Class Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Weight class 1 Weight class 1 to weight class 8 Indicates which weight class should be used when calculating the AS path weight Set the Action parameter to Accept and supply a valid BGP 3 weight class BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 15 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID BGP Communities to match Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies An empty list A list of BGP communities Specifies one or more BGP communities This policy applies to all BGP advertisements that match the list Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits t
84. ARNING SLOT 5 IP Code 56 Error when configuring static route 128 10 8 0 255 255 255 0 1 This message indicates that the static route is not configured at the time stated because all necessary MIB sets are not completed Error checking occurs as each attribute is set The router code generates the error messages to prevent misconfigured static routes You can verify that a static route has been created correctly by issuing a get command for the valid attribute in the wflIpStaticRouteEntry 10 instance Using the BCC Navigate to the global IP prompt and enter static route address lt destination gt mask lt ip_mask gt next hop address lt next_hop gt destination is the destination IP address jjp_mask is the mask of the destination IP address next_hop is the next hop IP address The static route prompt appears The BCC configures a static route with default values for all static route parameters and displays a static route specific prompt You customize a static route by modifying static route parameters Navigate to the static route specific prompt and enter lt parameter gt lt value gt parameter value is one of the parameter value pairs described in Table 4 1 308628 14 00 Rev 00 Configuring and Customizing IP for BGP Table 4 1 BCC Static Route Parameters Parameter Values Defaults Meaning Instructions state enabled default Specifies the state active or inactive of the disabled static route r
85. AS is not a member of any confederation If the list of confederation peers is empty nil no peers to this speaker exist among the neighbor ASs that are members of this local confederation You can use Site Manager or the BCC to configure this feature Using the BCC To configure the BGP confederation identifier navigate to the BGP prompt and enter confederation id lt AS_number gt AS_number is any valid autonomous system number The default is 0 For example the following BCC command sets the autonomous system number to 3 bgp confederation id 3 bgp To configure the BGP confederation peers navigate to the BGP prompt and enter confederation peers lt peer_address gt peer_address is any valid IP address for a BGP peer to the router you are configuring For example the following BCC command sets the BGP peer address to 1 1 1 1 bgp confederation peers 1 1 1 1 bgp 308628 14 00 Rev 00 5 17 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Configuration ID and the Confederation Peer parameters Click on Help or see the parameter descriptions beginning on page A 8 6 Click on OK Site
86. Accept and Announce Policies BCC Matching Parameters for BGP Accept Policies Parameter Values Function as path pattern null or an AS path Specifies an AS path that overrides the AS path attribute of a route matching this policy origin any default igp egp igp or egp incomplete incomplete or igp incomplete or egp Specifies the values of the BGP origin path attribute that apply to this policy aggregator as aggregator router AS number IP address Specifies an autonomous system This policy applies to BGP advertisements that contain in their aggregator path attribute this AS number Specifies a BGP router This policy applies to BGP advertisements that contain in their Aggregator path attribute this IP address as AS number Specifies an AS This policy applies to BGP advertisements from the peer in this AS community BGP community Specifies a BGP community This policy applies to all BGP advertisements that match the community network originating as IP address AS number Specifies a network ID to be included in the routing table in place of the network ID in the received advertisement Specifies an autonomous system This policy applies to BGP advertisements that originate from this AS peer IP address Specifies a BGP peer This policy applies to BGP advertisements from this peer The BCC treats this matching cr
87. Action ANNOUNCE Outbound Peers 1 1 1 1 2 2 2 2 Outbound AS 333 Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Add Name FilterMap Action ACCEPT Peer Address 1 1 1 1 2 2 2 2 Peer AS 333 Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies gt Add Name AggregateNets Action ANNOUNCE Network List 195 89 8 0 255 255 248 0 range Advertise List 195 89 8 0 255 255 248 0 255 255 255 255 255 255 255 255 continued C 4 308628 14 00 Rev 00 Translating Cisco to Nortel Networks Equivalents Table C 1 Cisco to Nortel Networks BGP Translation continued Item Cisco Configuration Text BCC Command Site Manager Logical Steps 12 aggregate address ip bgp lt cr gt Protocols gt IP gt Policy Filters gt BGP 4 gt 195 89 8 0 255 255 248 0 announce AggregateNets Announce Policies gt Add summary only action announce match Name AggregateNets network 195 89 8 0 Action ANNOUNCE 255 255 248 0 range back back Network List 195 89 8 0 modify advertise 195 89 8 0 255 255 248 0 range 255 255 248 0 Advertise List 195 89 8 0 255 255 248 0 13 router ospf 101 ip ospf as boundary router true OSPF AS Boundary Router YES redistribute bgp 2000 ip bgp intra as routing disabled Intra AS Disabled 14 router bgp 2000 ip bgp Announce Policy Name redistribute ospf 101 announce RedistributeOSPFtoBGP redistribute static RedistributeOSPFtoBGP Action ANNOUNCE action announce match Rout
88. BCC object When you press Enter the BCC creates the object and displays an object specific prompt To specify multiple parameter create multiple objects Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens Choose Policy Filters Choose BGP 4 The Policy Filters menu opens The BGP 4 menu opens al r oO py Choose Announce Policies The BGP4 Announce Policy Filters window opens continued 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Site Manager Procedure continued You do this System responds 6 Set the following parameters Enable Name Networks Action Rule Precedence Route Source Advertise From RIP Gateway Received on RIP Interface From OSPF Router ID Received OSPF Type Received OSPF Tag From EGP Peer From EGP AS From EGP Gateway From BGP Peer From BGP AS Received BGP Next Hop External Route Source Outbound Peer AS Outbound Peers Multi Exit Discriminator Multi Exit Discriminator Value Origin Replace As Path Local Preference Override Local Preference Value Next Hop Atomic AS Pattern BGP Community to announce BGP Community attribute action BGP Community to match AS Prepend
89. BCC or Site Manager to supply values that BGP can use to modify an attribute in a BGP update that matches the policy Using the BCC Navigate to the policy specific prompt and enter modify A modification prompt appears for the policy For example accept pol_1 bgp modify modify bgp accept pol_l To modify a parameter enter lt parameter gt lt value gt parameter value is one of the parameter value pairs described in Table 7 2 Table 7 2 BCC Modification Parameters for BGP Accept Policies Parameter Values local preference 0 default to 4 294 967 295 Function Specifies an override value for the local preference attribute med method Passthru default Indicates whether or not a multiexit Override discriminator metric is to be used for a Generate network matching this policy and what value Delete to use med 1 or an integer Specifies a metric for the multiexit discriminator attribute as path prepend List of AS numbers Specifies AS numbers that BGP adds to an AS path before it adds the current AS to the path inject List of IP addresses Specifies a list of networks that BGP advertises instead of the networks in the routing table The BCC treats this parameter as an object When you press Enter the BCC creates the object and displays an object specific prompt To specify multiple parameters create multiple objects 308628 14 00 Rev 00 Configuring BGP Accep
90. BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 5 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 5 B 26 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies Action Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies EGP Propagate BGP 3 BGP 4 Ignore Propagate Ignore Specifies whether or not to advertise a route that matches this policy To advertise the route specify Propagate To drop the route specify Ignore EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 6 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 6 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 6 308628 14 00 Rev 00 B 27 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Rule Precedence Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies 0 A metric value Specifies a m
91. BayRS Version 14 00 Part No 308628 14 00 Rev 00 September 1999 4401 Great America Parkway Santa Clara CA 95054 Configuring IP Exterior Gateway Protocols BGP and EGP NORTEL NETWORKS Copyright 1999 Nortel Networks All rights reserved Printed in the USA September 1999 The information in this document is subject to change without notice The statements configurations technical data and recommendations in this document are believed to be accurate and reliable but are presented without express or implied warranty Users must take full responsibility for their applications of any products specified in this document The information in this document is proprietary to Nortel Networks NA Inc The software described in this document is furnished under a license agreement and may only be used in accordance with the terms of that license A summary of the Software License is included in this document Trademarks NORTEL NETWORKS is a trademark of Nortel Networks Bay Networks AN BCN BLN and BN are registered trademarks and Advanced Remote Node ANH ARN ASN BayRS BayStack BCC and System 5000 are trademarks of Nortel Networks Microsoft MS MS DOS Win32 Windows and Windows NT are registered trademarks of Microsoft Corporation All other trademarks and registered trademarks are the property of their respective owners Restricted Rights Legend Use duplication or disclosure by the United States Government is subject to
92. Clara California 95054 8185 LICENSEE ACKNOWLEDGES THAT LICENSEE HAS READ THIS AGREEMENT UNDERSTANDS IT AND AGREES TO BE BOUND BY ITS TERMS AND CONDITIONS LICENSEE FURTHER AGREES THAT THIS AGREEMENT IS THE ENTIRE AND EXCLUSIVE AGREEMENT BETWEEN NORTEL NETWORKS AND LICENSEE WHICH SUPERSEDES ALL PRIOR ORAL AND WRITTEN AGREEMENTS AND COMMUNICATIONS BETWEEN THE PARTIES PERTAINING TO THE SUBJECT MATTER OF THIS AGREEMENT NO DIFFERENT OR ADDITIONAL TERMS WILL BE ENFORCEABLE AGAINST NORTEL NETWORKS UNLESS NORTEL NETWORKS GIVES ITS EXPRESS WRITTEN CONSENT INCLUDING AN EXPRESS WAIVER OF THE TERMS OF THIS AGREEMENT iv 308628 14 00 Rev 00 Contents Preface EDE e ee eee ee ee T Re er tee T E rere rr mere TA XV PTE MES E E ttre A E A N E ea dete meant eet xvi PRC OVNI sacsxerperdastexninsasiasenasinapenninseehaiainateniind cannes enigma xviii Hard Copy Technical MANUAIS isi cn nsiiscreaderietecieasrataorsaednoisu aaa iaa a aaien xix Fon to Get HEI cece acevaceesicacak ices acetie dn chica seed aaa a XX Chapter 1 Exterior Gateway Protocols BGP EGP Mia Galonar PPC Ole DO xacieccc occa se siudanctsats decane e aa 1 1 Border Gateway Protocol BGP scnssspusaxasageat a a 1 3 Exterior Gateway Proloco EGP ornans a a kaa aAa 1 3 Classless Interdomai RONING arsson naa eoan a 1 4 BGP Conceps and Tr ily sainia i AA ENN 1 4 Paari Peal SOE VG mranoimer ian A on daamedemenas 1 5 Stub and Multihomed Autonomous Systems oc isisccces secerssscoscner
93. Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 6 5 Configuring IP Exterior Gateway Protocols BGP and EGP Negotiating the BGP Version BGP peers negotiate the version of BGP that they will use to exchange routing information If you enable both BGP 3 and BGP 4 the router first attempts to use BGP 4 If the BGP peer is not a BGP 4 speaker the router uses BGP 3 By default BGP considers BGP 4 as both the minimum and maximum acceptable version for negotiation You can use the BCC or Site Manager to specify BGP 3 as the minimum or maximum acceptable version Using the BCC To specify the minimum version navigate to a BGP peer prompt and enter min version lt version gt version is one of the following bgp3 bgp4 default To specify the maximum version navigate to a BGP peer prompt and enter max version lt version gt version is one of the following bgp3 bgp4 default 6 6 308628 14 00 Rev 00 Using Site Manager Establishing a Peer to Peer Session Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens want to edit BGP peer parameters 6 Click on BGP Peers 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which
94. E sinana R A 3 6 Customizing EGP soeriisiireris TE iaai en oboed T ibocan dii ednet nod Using he Circuitless IP Umea isernia 3 6 Configuring an Unnumbered IP Interface ccccseeeeeeeeeceeeeeeeeeseceeeeeaeeeeeeeeesaeesseneees 3 7 Using BGP Peers with an Unnumbered Interface c ccccccceeeseeeceeeeeeeeaeeeeeeeeses 3 7 Chapter 4 Configuring and Customizing IP for BGP Customizing IP Global Parameters 00 8 er began arbeba steels MT oiai 4 1 Navigating the BCC to the IP Global Prompt sisirin iniri 4 2 Opening the Site Manager Window for IP Global Parameters ccsceseeeeee 4 3 Disabling and Reenabling Global IP E E E T 4 3 Configuring the Router for Forwarding Mode seeseeesseessesssessssssrrrssrrsssrnssrnresrnnes 4 4 Enabling Eguak Gost Multipath SUPPOTE essuissiusuisiannsnainnnn saoter aiana 4 5 Enabling ISP Mode o the OU cca dccecentes a adesinonesiahite asdiedaedacadeaiedecniea ar 4 7 Deming a SRSA RONE araa SN a say Satis 4 9 Deining a Stale Defaut ROUS reniri A A 4 13 Defining 4 Static Black Hole for a SUPErnEt sccscssiscesckccasecdacsiateascioncssededecnteteasiedance 4 14 vi 308628 14 00 Rev 00 Chapter 5 Configuring and Customizing BGP Comgurnd BEGP GIGI idre n i E e E Aaa 5 1 Enabingand Disabling BGP icc acsssssanssarenuivanitl ential EN E Supplying a BGP Identifier 0 0 0 0 P E ences aiei T P paies iaa DA dentying the Local AS scriciticscsninissnina a 5 5 Disabling and Re
95. Estimated Hosts parameter A 48 Estimated Networks parameter A 47 Ethernet Arp Encaps parameter A 37 Exterior Gateway Protocol EGP 2 1 3 External Advertisement Timer parameter 6 10 A 13 external advertisement timer setting for BGP peers 6 9 F Forward Cache Size parameter A 41 forwarding command 4 4 forwarding mode configuring 4 4 Forwarding parameter global IP 4 5 A 44 FRM Broadcast parameter A 38 FRM Cast 1 DLCI parameter A 39 FRM Cast 2 DLCI parameter A 39 308628 14 00 Rev 00 G Gateway Mode parameter EGP neighbor 3 5 10 10 A 25 gateway protocols 1 1 H Hello Timer parameter 10 14 holddown command BGP peers 6 11 Holdtime parameter 6 11 A 14 Host Cache parameter A 34 Host Encapsulation parameter A 55 host only functions configuring 4 4 host only mode configuring global IP for 4 4 IBGP interior BGP 1 6 IBGP ECMP Method parameter 9 5 ibgp ecmp method command 9 4 Identifier parameter BGP 3 2 A 2 implementation notes EGP 10 5 inject time command 5 9 interior gateway protocol IGP 1 3 Internet service provider ISP mode 4 7 intra as routing command 5 6 IP equal cost multipath 4 5 global enabling and disabling 4 3 forwarding mode 4 4 starting 3 1 IP Address parameter BGP 3 2 EGP 3 5 IP configuration A 28 isp mode command 4 8 Index 3 K keepalive command BGP peer 6 8 Keepalive Timer parameter 6 8 A 14 L Local Addres
96. Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable ISP Mode Support Configuration Manager gt Protocols gt IP gt Global Disable Enable Disable Enables and disables internet service provider ISP features Use this parameter to configure BGP as a soloist and to disable the use of forwarding tables on IP interfaces 1 3 6 1 4 1 18 3 5 3 2 1 1 19 IBGP ECMP Enable Configuration Manager gt Protocols gt IP gt Global Disable Enable Disable Allows BGP to select an IP route to the IBGP next hop using available ECMP routing information supplied by the IGP RIP or OSPF used in the AS Make sure that ECMP is enabled for the IGP used in the AS 1 3 6 1 4 1 18 3 5 3 2 1 1 23 Percentage of ARP Buffers Configuration Manager gt Protocols gt IP gt Global 100 An integer indicating the percentage of buffers Defines the upper limit as a percentage of buffers that ARP can use for saving buffers when resolving ARP requests Specify the percentage as an integer 1 3 6 1 4 1 18 3 5 3 2 1 1 27 A 50 308628 14 00 Rev 00 Site Manager Parameters Static Route Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt Static Routes This parameter def
97. GP 4 Preference Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies 1 1 to 16 Specifies a value that can be used to compare a route that matches this policy with other BGP 4 routes The larger the value the greater the preference To indicate maximum preference enter 16 This parameter is valid only if the Action parameter is set to Accept 1 3 6 1 4 1 18 3 5 3 2 6 9 1 17 AS Weight Class Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Weight class 1 Weight class 1 to weight class 8 Indicates which weight class value should be used when calculating the AS path weight Enter a valid BGP 4 weight class This parameter is valid only if the Action parameter is set to Accept 1 3 6 1 4 1 18 3 5 3 2 6 9 1 18 B 16 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies AS Pattern Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Empty string Any regular expression or empty string Allows AS_PATH pattern matching Enter a valid regular expression to indicate an AS and its position in a path The policy applies to all routes whose AS path incl
98. GP Communities to Match Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies An empty list A list of BGP communities Specifies one or more BGP communities This policy applies to all BGP advertisements that match the list Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means match any list 1 3 6 1 4 1 18 3 5 3 2 6 8 1 31 B 46 308628 14 00 Rev 00 Routing Policies BGP 4 Specific Announce Policy Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID External Route Source Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Any Direct Static RIP OSPF with Type 2 metric EGP BGP Any Specifies one or more external route source identifiers If you specify an external route source a route from that source that meets the other criteria of this policy matches the policy This parameter applies only to OSPF routes that use the new ASE type 2 metric The protocol from which OSPF received the route is encoded in the ASE metric along with the route s metric To specify any external route source use the default BGP 4 1 3 6 1 4 1 18 3 5 3
99. Hop AS destination_1 BGP 4 577438 126992 F 1 764 destination_2 BGP 4 577438 126992 F 4 764 destination_3 BGP 4 577438 126992 F 1 764 Figure 9 2 IBGP ECMP Route Balancing If you configure BGP for traffic balancing BGP submits multiple BGP routes one for each OSPF ECMP route in the following manner 1 BGP submits two IP routes to destination_1 One route specifies interface 1 the second route specifies interface 4 2 BGP submits two IP routes to destination_2 One route specifies interface 1 the second route specifies interface 4 3 BGP submits two IP routes to destination_3 One route specifies interface 1 the second route specifies interface 4 308628 14 00 Rev 00 9 3 Configuring IP Exterior Gateway Protocols BGP and EGP Figure 9 3 shows the six traffic balancing BGP ECMP entries to the routing table on router 4 Destination Mask Proto Age Cost Next Hop AS destination_1 BGP 4 577438 126992 F 1 764 destination_1 BGP 4 577438 126992 F 4 764 destination_2 BGP 4 577438 126992 F 1 764 destination_2 BGP 4 577438 126992 F 4 764 destination_3 BGP 4 577438 126992 F 1 764 destination_3 BGP 4 577438 126992 F 4 764 Figure 9 3 IBGP ECMP Traffic Load Balancing You can use the BCC or Site Manager to configure IBGP for ECMP route balancing and traffic load balancing Using the BCC Navigate to the BGP global prompt and enter ibgp ecmp method lt method gt method is one of the values described in Table 9 1
100. ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Multi Exit Discriminator Value Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies 1 A value to use as the multi exit discriminator Specifies the value to use as the multi exit discriminator This is valid only if the Action parameter value is accept and if the Multi Exit Discriminator parameter is set to override or generate and there is MED present Enter the name of a configured route flap dampening template or accept the default template 1 3 6 1 4 1 18 3 5 3 2 6 9 1 22 Name Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap None An alphanumeric string up to 20 characters Identifies the name of the route flap dampening template Enter a string that uniquely identifies the route flap dampening template 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 3 Cutoff Threshold Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 2000 1 to 20000 Specifies the maximum threshold for the route penalty value If the penalty value rises above the value for this parameter BGP suppresses the route The router increments the penalty value by 1000 for each withdrawal and increments it by 500 for each reachable announ
101. INCOMPLETE Choose the route with the lower Multi Exit Discriminator attribute routes without a MED are assumed to have a max MED Choose the route with the lower interior cost to the Next Hop Choose external BGP over IBGP Choose the route with the lower BGP identifier Choose the route with the lower BGP connection remote address Choose the route with the lower BGP connection local address 308628 14 00 Rev 00 C 11 Configuring IP Exterior Gateway Protocols BGP and EGP Regular Expression Symbols Table C 4 lists the characters used in Cisco and Nortel Networks regular expressions Table C 4 Regular Expression Symbols Name Symbol Meaning period Matches any single character including white space asterisk j Matches 0 or more sequences of the pattern Plus sign Matches 1 or more sequences of the pattern Question mark Matches 0 or 1 occurrences of the pattern caret A Matches the beginning of the input string Dollar sign Matches the end of the input string underscore _ Matches a comma left brace right brace left parenthesis right parenthesis the beginning of the input string the end of the input string or a space brackets Designates a range of single character patterns Hyphen Separates the end points of a range 308628 14 00 Rev 00 Translating Cisco to Nortel Networks Equivalents Nortel Networks AS _ Path Pattern Matching Symbols Ta
102. IP gt Policy Filters gt EGP gt Accept Policies An empty list A list of IP addresses Specifies the IP address of one or more EGP gateways This policy applies to EGP advertisements that use these gateways as the next hop Use the default empty list to indicate that this policy applies to EGP advertisements with any gateway address EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 12 B 8 308628 14 00 Rev 00 Routing Policies BGP 3 Specific Accept Policy Parameters Parameter Injection List Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Default An empty list Options A list of network identifiers Function Specifies network IDs to be included in the routing table in place of the network IDs listed in the received advertisement Instructions Specify a non null value only if the Action parameter is set to Accept The values you enter in the injection list determine the action taken If you supply a list of network IDs these IDs are injected into the routing table instead of the actual received IDs If you use the default an empty list the actual received network IDs are injected into the routing table If you supply a list that includes the encoding 255 255 255 255 255 255 255 255 the actual received network IDs are injected into the routing table along with the other Ds in the injection list This allows insertion of an aggregate or default along with the actual netwo
103. IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the addresses of one or more interfaces on this router This policy applies to RIP advertisements received on the interfaces in this list and applies only to RIP sourced routes and if RIP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to RIP updates received on any interface EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 12 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 12 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 12 B 32 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies From OSPF Router ID Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the IDs of one or more OSPF routers This policy applies to OSPF advertisements authored by a router on this list and applies
104. IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies None Any alphanumeric character string Identifies this policy Enter a unique name for the policy EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 4 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 4 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 4 308628 14 00 Rev 00 B 25 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Networks Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of network identifiers Each identifier consists of a network number a mask and a flag to indicate whether the ID refers to a specific network or a range of networks Specifies which networks will match this policy Enter a specific encoding of 0 0 0 0 0 0 0 0 to match the default route Enter a range encoding of 0 0 0 0 0 0 0 0 to match any route Enter an empty list to match any route EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 5
105. Licensee for damages in any form solely by reason of the termination of this license 8 Export and Re export Licensee agrees not to export directly or indirectly the Software or related technical data or information without first obtaining any required export licenses or other governmental approvals Without limiting the foregoing Licensee on behalf of itself and its subsidiaries and affiliates agrees that it will not without first obtaining all export licenses and approvals required by the U S Government i export re export transfer or divert any such Software or technical data or any direct product thereof to any country to which such exports or re exports are restricted or embargoed under United States export control laws and regulations or to any national or resident of such restricted or embargoed countries or ii provide the Software or related technical data or information to any military end user or for any military end use including the design development or production of any chemical nuclear or biological weapons 9 General If any provision of this Agreement is held to be invalid or unenforceable by a court of competent jurisdiction the remainder of the provisions of this Agreement shall remain in full force and effect This Agreement will be governed by the laws of the state of California Should you have any questions concerning this Agreement contact Nortel Networks 4401 Great America Parkway PO Box 58185 Santa
106. NAP LSAP encapsulation 1 3 6 1 4 1 18 3 5 3 2 1 24 1 26 SMDS Group Address Configuration Manager gt Protocols gt IP gt Interfaces The SDMS configured address A complete SMDS E 164 address specified by the SMDS subscription agreement that you have with your SMDS provider Provides a MAC layer multicast address for this IP interface in an SMDS network This parameter is displayed only if this is an SMDS circuit Enter an entire E 164 address for example E1 617 555 1212 FFFF If you do not supply an address IP uses the SDMS configured address To configure this parameter for a multinet or multigroup configuration see Configuring SMDS 1 3 6 1 4 1 18 3 5 3 2 1 24 1 20 308628 14 00 Rev 00 A 37 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID SMDS Arp Request Address Configuration Manager gt Protocols gt IP gt Interfaces The SDMS configured address A complete SMDS E 164 address specified by the SMDS subscription agreement that you have with your SMDS provider Provides an address resolution multicast address for this IP interface in an SMDS network This parameter is displayed only if this is an SMDS circuit Enter an entire E 164 address for example E1 617 555 1212 FFFF If you do not supply an address IP uses the SDMS configure
107. No Signature event and discards the packet but does not close the TCP connection When TCP receives a packet with the kind 19 option it first verifies that an MD5 authentication key has been configured for the TCP connection e If the key has not been configured TCP logs a TCP MD5 No Key Configured event and discards the packet but does not close the TCP connection e If the key has been configured TCP computes the expected MDS signature and compares the computed signature with the received MDS signature If the signatures match TCP sends the packet to BGP If the signatures do not match TCP logs a TCP MD5 Invalid Signature event and discards the packet but does not close the TCP connection e The occurrence of any of these errors increments the total count of TCP connection MDS errors wfTcpConnMd5Errors You can enter an optional variable length ASCII authentication key for each BGP peer This key is stored in the wfBgpPeerTcpMd5Key MIB object Entering the authentication key also enables authentication for the peer connection Both peers must be configured with the same authentication key When an authentication key is stored in the MIB or the configuration file it can optionally be encrypted using DES with the NPK MEK key as selected by the wfBgpPeerTcpMd5 KeyStorage MIB object By default BGP 4 MD5 authentication is disabled Use the Technician Interface secure shell or the Site Manager WEP Key Manager to ent
108. OUNCE match ip address 1 network 192 10 20 0 Network List gt List set metric 100 255 255 255 0 range back Network Number 192 10 20 0 route map outbound peer 1 1 1 1 Network Mask 255 255 255 0 AdvertiseMap permit 20 back back Match Criteria range set metric 50 modify Multi Exit Discriminator Specified access list 1 permit med method specified Multi Exit Discriminator Value 100 192 10 20 0 0 0 0 255 med 100 Rule Precedence 2 Outbound Peers 1 1 1 1 ip bgp announce AdvertiseMapOther Protocols gt IP gt Policy Filters gt BGP 4 gt action announce Announce Policies gt Add precedence 1 modify Name AdvertiseMapOther med method specified Action ANNOUNCE med 50 Multi Exit Discriminator Specified match outbound peer 1 1 1 1 Multi Exit Discriminator Value 50 Rule Precedence 1 Outbound Peers 1 1 1 1 8 ip bgp Protocols gt IP gt Policy Filters gt BGP 4 gt neighbor 1 1 1 1 filter list 5 in lp as path access list 5 permit 41000 5000 accept IncomingRoutes action accept match as path pattern 41000 5000 peer 1 1 1 1 Accept Policies gt Add Name IncomingRoutes Action ACCEPT AS Pattern 1000 45000 Peer Address 1 1 1 1 continued 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Table C 1 Cisco to Nortel Networks BGP Translation continued Item Cisco Configuration Text BCC Command Site Manager Logical Steps 9 neighbor 1 1 1 1 filter list ip bgp Protocols
109. Options Function Instructions MIB Object ID Site Manager Parameters Next Hop Mask Configuration Manager gt Protocols gt IP gt Static Routes 0 0 0 0 Any valid subnet mask address Specifies the subnet mask of the next hop router The parameter also defines a black hole route for a supernet Enter the subnet mask in dotted decimal notation To configure a black hole static route enter 255 255 255 255 If you are configuring a static route to an unnumbered interface enter 0 0 0 0 1 3 6 1 4 1 18 3 5 3 2 1 5 1 7 Preference Configuration Manager gt Protocols gt IP gt Static Routes 16 1 to 16 Specifies a weighted value from 1 to 16 with 16 being the most preferred that the IP router uses to select a route when its routing tables contain multiple routes to the same destination Enter a value from 1 to 16 for this static route To configure a black hole static route enter the maximum preference value 1 3 6 1 4 1 18 3 5 3 2 1 5 1 8 Unnumbered CCT Name Configuration Manager gt Protocols gt IP gt Static Routes None A valid circuit name Specifies the local router circuit associated with the static route over an unnumbered interface An entry for a route using an unnumbered interface must include the circuit associated with the interface Use this parameter to specify that circuit name 1 3 6 1 4 1 18 3 5 3 2 1 5 1 11 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP a
110. P gt EGP Enable Enable Disable This parameter allows you to globally enable or disable EGP on all router interfaces Set to Disable if you want to disable EGP for the entire router Set to Enable if you previously disabled EGP and now want to reenable it 1 3 6 1 4 1 18 3 5 3 2 4 1 2 Local Autonomous System ID Configuration Manager gt Protocols gt IP gt EGP None 1 to 65 535 Identifies the local autonomous system the AS to which this router belongs by the NIC assigned decimal number There is no default for this parameter Either accept the current value for this parameter or enter a new value 1 3 6 1 4 1 18 3 5 3 2 4 1 7 A 24 308628 14 00 Rev 00 Site Manager Parameters EGP Neighbor Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Remote Peer IP Address Configuration Manager gt Protocols gt IP gt EGP gt Neighbors Null Any IP address Specifies the IP address of the remote router that will form an EGP neighbor relationship with this router Enter the IP address in dotted decimal notation 1 3 6 1 4 1 18 3 5 3 2 4 3 1 4 Gateway Mode Configuration Manager gt Protocols gt IP gt EGP gt Neighbors Core Core Non Core Specifies the gateway mode for this EGP neighbor If you choose Core the default the local AS to which this EGP neighbor belongs will
111. P Packets e eee PEE 5 24 Disabling BayRS Local Preference Calculation and Route Selection 20 5 26 Calculating BGP 4 Local Preference Values ccccesccececssseeeeesseeeeesseseeesseeaeens 5 27 Best OUTS SOI CUOMN iraire a a E eN EESE 5 28 Coniguing BGP Message Logging aenuncnroiniainihnh anini 5 30 Configuring EBGP Route Flap Dampening sses PEE PET Teau aa 308628 14 00 Rev 00 vii Chapter 6 Establishing a Peer to Peer Session Defining a Peetro Foer SSSI ospica nnr eea r eiar ia 6 2 Initiating a Peer to Peer SCSSION aunnrninaininn a a A Negotiating the BGP Version ere P R re are Cre Cre pean satin OG Reel the Connection ANE oiiaii cates taeda pheeninaiaieniaelaNs 6 7 Setting the External Advertisement Timer ccccceseeeceeeeeeeeeeeeeeeeeeeaeeseeeeeeeeaeeeeeaaeeeed 6 9 SDRC a FHolddown TIME seedaxctniecpace satin Jaiaccnastsdncedannesacel adentasesanueidocecdaedesountenestiedane 6 10 Setting a Minimum AS Origination Interval cccceceeeeseeeeeeeeeeeeeeeaeeeeeeeeeeaeeeeeneeee 6 12 Overriding the Local AS Number T agehal aonni eer T A 6 14 Speciying a Maximum Update S26 seiniin a ai E 6 14 Setting the Route Echa GWION seriinin aani aN a aaa 6 16 Disabling and Reenabling Loop Detection PEE E E T ee 6 17 Specifying the Route Reflector Mode of the Remote Peer csceseseeeseeteeeseeeeenes 6 18 Configuring Peers over an Unnumbered Point to
112. P parameters You customize BGP by modifying BGP parameters as described in Chapter 5 Configuring and Customizing BGP Step 2 Defining a Peer to Peer Connection BGP exchanges routing information with BGP peers located in another autonomous system AS or within the same AS To define a peer to peer connection navigate to the BGP prompt and enter peer local lt ocal_ip_address gt remote lt remote_ip_address gt as lt as_number gt local_ip_adadress is the address expressed in dotted decimal format of an IP interface on the local router remote_ip_address is the address of an IP interface on the remote peer s router as_number is the number of the AS in which the remote peer is located For example the following command defines a peer to peer connection between local IP interface 2 3 3 3 and remote interface 2 3 3 4 The remote BGP peer is located in AS 4 bgp peer local 2 3 3 3 remote 2 3 3 4 as 4 peer 2 3 3 3 2 3 3 4 The BGP peer to peer relationship is established with default values for all BGP peer parameters You customize the peer to peer connection by modifying BGP peer parameters as described in Chapter 6 Establishing a Peer to Peer Session 308628 14 00 Rev 00 2 3 Chapter 3 Starting BGP and EGP Services with Site Manager This chapter describes how to use Site Manager to start the following IP services using a basic configuration that is a configuration using only default value
113. Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Proxy Configuration Manager gt Protocols gt IP gt Interfaces Disabled Enabled Disabled Specifies whether this interface uses Proxy ARP to respond to ARPs for a remote network Select Enabled to enable Proxy ARP on this interface In order to enable Proxy ARP you must have set the ARP parameter to Enable for this interface When you enable Proxy ARP the IP router assumes responsibility for IP datagrams destined for the remote network To enable Proxy ARP for subnets reachable via a default route also set the Enable Default Route for Subnets parameter to Enable To enable Proxy ARP for remote destinations on other networks set the Nonlocal ARP Destination parameter to Accept Select Disabled to disable Proxy ARP on this interface 1 3 6 1 4 1 18 3 5 3 2 1 24 1 16 Host Cache Configuration Manager gt Protocols gt IP gt Interfaces Off Off 120 180 240 300 600 900 1200 seconds Specifies whether the IP router times out entries in the address resolution cache for this interface and specifies the timeout interval in seconds if the interface does time out entries The address resolution cache contains host physical addresses learned by means of ARP or Proxy ARP A host entry is timed out deleted if the IP router sends no traffic destined for that host
114. Protocols gt IP gt Interfaces None XX00000000000000 to FEFFFFFFFFFFFF Defines the user part suffix of the ATM address for the ATM ARP server on your network The user part consists of a 6 byte end station identifier and a 1 byte selector field Enter the user part suffix of the ATM ARP server on your network A complete ATM address consists of a network prefix and a user part Use the ARP Server ATM Address Network Prefix parameter to supply the network part of the ATM address 1 3 6 1 4 1 18 3 5 3 2 1 24 1 113 Registration Refresh Interval Configuration Manager gt Protocols gt IP gt Interfaces 900 seconds for a client 1 200 seconds for a server Any interval in seconds For a client this parameter specifies the interval between registration refreshes For a server this parameter specifies the duration for which the registration is valid Determine whether ATMARP is running as a client or as a server on this interface and enter an appropriate value 1 3 6 1 4 1 18 3 5 3 2 1 24 1 115 TR Endstation Arp Type Configuration Manager gt Protocols gt IP gt Interfaces STE STE ARE Specifies the ARP type for an interface configured for token ring support For spanning tree explorer STE ARP packets use the default For all route explorer ARE packets select ARE Set the TR Endstation parameter to on 1 3 6 1 4 1 18 3 5 3 2 1 24 1 127 308628 14 00 Rev 00 A 43 Configuring IP Exterior Gateway Prot
115. SCII authentication key for each BGP 4 peer This key is stored in the wfBgpPeerTcpMd5Key MIB object Entering the authentication key also enables authentication for the peer connection Both peers must be configured with the same authentication key When an authentication key is stored in the MIB or the configuration file it can optionally be encrypted using DES with the NPK MEK key as selected by the wfBgpPeerTcpMd5KeyStorage MIB object You can enter the authentication keys through Site Manager or the BCC Use the Technician Interface secure shell to enter the NPK MEK 5 22 308628 14 00 Rev 00 Configuring and Customizing BGP Configuring BGP Authentication You can configure BGP MD5 authentication using the BCC or Site Manager This guide describes how to configure the BGP TCP MD5 authentication attributes with the BCC and Site Manager interfaces The BCC Site Manager and secure shell interfaces accept and display the authentication keys as unencrypted character strings regardless of whether the underlying storage is clear or encrypted That is these interfaces can encrypt a key before saving it and decrypt it before displaying it They also handle the necessary conversion from character string to octet string The Technician Interface however displays a key just as it is stored in the MIB The attributes that you must configure within the MIB entry wfBgpPeerEntry are wfBgpTcpAuthentication which enables authentication wfBgpP
116. Table 9 1 IBGP ECMP Methods Method Meaning route balance BGP submits one BGP route to the IP routing table for each BGP destination using in turn round robin the available IGP ECMP routes to the next hop traffic balance BGP submits multiple routes to IP using all Known IGP ECMP IP next hops For example the following command configures BGP for IBGP ECMP traffic load balancing bgp ibgp ecmp method traffic balance bgp 308628 14 00 Rev 00 Configuring Route and Traffic Load Balancing Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the IBGP ECMP Method parameter Click on Help or see the parameter descriptions beginning on page A 8 6 Click on OK Site Manager returns you to the Configuration Manager window Configuring EBGP for Route and Traffic Load Balancing EBGP route balancing and traffic load balancing are two techniques that allow an EBGP speaker to distribute routes to the same destination among multiple equal cost paths In both techniques EBGP uses equal cost multipath ECMP routes submitted statically to the IP routing table Although unusual for EBGP connections the ECMP routes could also be submitted by OSPF o
117. act as a transit AS That is it will advertise networks that reside within the AS as well as within external networks If you choose Non Core the AS to which this EGP neighbor belongs will act as a stub AS That is it will advertise only networks that reside within the AS Set this parameter to either Core or Non Core depending on how you want this EGP neighbor to function 1 3 6 1 4 1 18 3 5 3 2 4 3 1 5 308628 14 00 Rev 00 A 25 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt EGP gt Neighbors Enable Enable Disable Enables or disables an EGP neighbor relationship with the specified IP address Set this parameter to Disable if you want to temporarily disable this neighbor relationship rather than delete it Or set it to Enable if you previously disabled this neighbor relationship and now want to reenable it 1 3 6 1 4 1 18 3 5 3 2 4 3 1 2 Acquisition Mode Configuration Manager gt Protocols gt IP gt EGP gt Neighbors Passive Passive Active Specifies which of the two neighbors initiates EGP connections The router in the active mode is the initiator Set this parameter to Active if yo
118. all zero subnet address and an all zero broadcast address are both valid the router cannot distinguish an all subnets broadcast from a directed broadcast for the zero subnet 1 3 6 1 4 1 18 3 5 3 2 1 1 10 Estimated Networks Configuration Manager gt Protocols gt IP gt Global 0 0 to 2 147 483 647 Allows the IP software to preallocate system resources based on the anticipated size of the routing table Preallocation of memory increases the speed with which IP software can learn routes because it removes the overhead caused by dynamic memory allocation Preallocation also makes better use of memory and reduces the amount of memory required Set to the number of networks including unique subnets that you expect Avoid using a number that is excessively large This will cause a wasteful overallocation of memory If you use the default value 0 IP software preallocates memory for 500 routing table entries 1 3 6 1 4 1 18 3 5 3 2 1 1 11 308628 14 00 Rev 00 A 47 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Estimated Hosts Configuration Manager gt Protocols gt IP gt Global 0 0 to 2 147 483 647 Allows the IP software to preallocate system resources based on the anticipated size of the routing table Preallocation of memory increase
119. and may also introduce forwarding loops 308628 14 00 Rev 00 5 11 Configuring IP Exterior Gateway Protocols BGP and EGP Using the BCC Navigate to the BGP prompt and enter multi hop lt state gt state is one of the following enabled disabled default For example the following command enables BGP for multihop peer to peer connections bgp multi hop enabled bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Multi hop EBGP Connection parameter Click on Help or see the parameter description on page A 5 6 Click on OK Site Manager returns you to the Configuration Manager window 5 12 308628 14 00 Rev 00 Configuring and Customizing BGP Disabling and Reenabling Dynamic Policy Configuration By default BGP reconfigures IP policies dynamically This means that if you modify a policy BGP dynamically reevaluates all affected routes in the light of the modified policy BGP then sends the appropriate withdraw or update message to the affected peers BGP keeps track of the routes sent to each peer allowing for precise determination of which routes to send and which to withdraw If you modify an IP policy with this feature
120. arameter values for that interface appear in the window 6 Set the Acquisition Mode parameter Click on Help or see the parameter description on page A 26 7 Click on Apply and then click on Done Site Manager returns you to the Configuration Manager window 10 12 308628 14 00 Rev 00 Choosing the Poll Mode Customizing EGP Services The type of neighbor reachability algorithm executed by the local EGP neighbor is called the poll mode There are two poll modes active and passive In the active mode a router sends hello and poll messages to request reachability status from its neighbor In the passive mode a router responds to hello and poll messages with I H U and update messages By default EGP is configured to execute both the active and passive poll mode You can use Site Manager to execute the active or passive mode only Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose EGP The EGP menu opens 4 Choose Neighbors The IP Interface List for EGP window opens 5 Click on the IP interface you want The parameter values for that interface appear in the window 6 Set the Poll Mode parameter Click on Help or see the parameter description on page A 26 7 Click on Apply and then click on Done Site Manager returns you to the Configuration Manager wind
121. at are available when you configure the EGP neighbors at each end of a connection However Nortel Networks recommends that one router be configured in the active acquisition mode and the other in the passive acquisition mode 308628 14 00 Rev 00 10 3 Configuring IP Exterior Gateway Protocols BGP and EGP In the neighbor reachability phase EGP is responsible for monitoring and maintaining an established EGP neighbor relationship between two routers Its purpose is to ensure that the neighbors are operational and can provide reliable network reachability information Two neighbors will be able to exchange network reachability information only if they are both in the up state and know that they are both in the up state This is the point at which neighbor reachability is positively determined In the network reachability phase EGP is responsible for determining which networks are reachable through two EGP neighbors that is it provides the network reachability information This information provides a list of gateways the networks those gateways can reach and their associated distances Two neighbors determine network reachability by exchanging poll messages and routing update responses as follows e The active neighbor sends a poll message to a passive neighbor that it already knows to be reachable The poll message requests routing information from the passive neighbor e The routing update response contains the routing information
122. at the Destination IP Address parameter Specifies the subnet mask of the destination network Specifies the supernet mask of the supernet for which you want to configure a black hole static route Enter the subnet or supernet mask in dotted decimal notation To configure a default route enter 0 0 0 0 To configure a black hole static route enter a supernet mask 1 3 6 1 4 1 18 3 5 3 2 1 5 1 4 Cost Configuration Manager gt Protocols gt IP gt Static Routes 1 1 to the value of the RIP Diameter parameter maximum 126 Specifies the number of router hops a datagram can traverse before reaching the destination IP address The IP router uses the cost value when determining the best route for a datagram to follow Enter the number of router hops 1 3 6 1 4 1 18 3 5 3 2 1 5 1 5 Next Hop Addr Configuration Manager gt Protocols gt IP gt Static Routes 0 0 0 0 Any valid IP address Specifies the IP address of the next hop router Defines a black hole route for a supernet Enter the IP address in dotted decimal notation To configure a black hole static route enter 255 255 255 255 If you are configuring a static route to an unnumbered interface enter 0 0 0 0 1 3 6 1 4 1 18 3 5 3 2 1 5 1 6 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default
123. ath attribute an AS number on this list To specify that the policy applies to BGP advertisements with any AS number in the Aggregator path attribute use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 14 Aggregator Router List Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of IP addresses Specifies one or more BGP routers This policy applies to BGP advertisements that contain in their Aggregator path attribute an IP address on this list To specify that this policy applies to BGP advertisements with any router address in the Aggregator path attribute use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 15 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Local Preference Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies 0 0 to 4 294 967 295 Assigns a local preference value to a route matching this policy This value overrides the calculated value for EBGP routes or the Local Preference path attribute for IBGP routes To indicate a preference enter a value from 1 to 4 294 967 295 1 3 6 1 4 1 18 3 5 3 2 6 9 1 16 B
124. ath to 192 32 2 0 you can assign one weight class to the AS in the path to network 192 32 1 0 and another class to the AS in the path to 192 32 2 0 When a BGP router receives a new route it evaluates the route against any existing accept policies If after this evaluation the path still is to be used the router calculates the total weight of the path Configure the same AS weights on all BGP routers in an AS 308628 14 00 Rev 00 6 21 Configuring IP Exterior Gateway Protocols BGP and EGP You can use Site Manager to assign a weight and a weight class to an AS Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Weights The BGP AS Weight Parameters window opens 5 Click on Add The BGP AS Weights window opens 6 Set the following parameters e AS Weight Value 1 through 8 Click on Help or see the parameter descriptions beginning on page A 19 Click on OK Site Manager returns you to the BGP AS Weight Parameters window 6 22 308628 14 00 Rev 00 Chapter 7 Configuring BGP Accept and Announce Policies BGP accept and announce policies govern which routes a router uses and which routes it propagates to other routers Appendix B Routing Policies describes the BGP accept and announce policy pa
125. ation Manager window choose Protocols System responds The Protocols menu opens want to edit BGP peer parameters 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you 6 Click on BGP Peers 7 Click on the peer for which you want to edit parameters The BGP Peer List window opens The parameters for that peer appear in the window Set the Holdtime parameter Click on Help or see the parameter description on page A 14 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 6 11 Configuring IP Exterior Gateway Protocols BGP and EGP Setting a Minimum AS Origination Interval By default a BGP speaker that issues an update to advertise a change in the AS must wait at least 15 seconds before advertising a subsequent change You can use the BCC or Site Manager to specify a different interval Using the BCC Navigate to a BGP peer specific prompt and enter min originate time lt seconds gt seconds is an integer indicating the minimum number of seconds that BGP waits between advertisements For example the following command causes BGP to wait at least 30 seconds between updates on the peer session established between interfaces 2 2 2 2 and 2 2 2 5 peer 2 2 2 2 2 2 2 5 5 mi
126. attribute matches an IP address on this list and applies only to BGP sourced routes and if BGP is included as a route source bgp peer List of IP Specifies the IP address of one or more BGP addresses peers This policy applies to BGP advertisements authored by a router on this list and applies only to BGP sourced routes and if BGP is included as a route source egp as List of AS numbers Specifies one or more autonomous system numbers This policy applies to EGP advertisements received from EGP peers in an AS on this list and applies only to EGP sourced routes and if EGP is included as a route source egp gateway egp peer inbound interface List of IP addresses List of IP addresses List of IP addresses Specifies the IP address of one or more EGP gateways This policy applies to EGP advertisements that use a gateway on this list as the next hop and applies only to EGP sourced routes and if EGP is included as a route source Specifies the IP address of one or more EGP peers This policy applies to EGP advertisements authored by a router on this list and applies only to EGP source routes and if EGP is included as a route source Specifies the address of one or more interfaces on this router This policy applies to RIP advertisements received on the interfaces in this list and applies only to RIP sourced routes and if RIP is included as a route source continued 308628 14 00 Rev 00
127. aults to Enable when you configure the static route Enable Disable Specifies the state active or inactive of the static route record in the IP routing tables Select Disable to make the static route record inactive in the IP routing table the IP router will not consider this static route Select Enable to make the static route record active again in the IP routing table 1 3 6 1 4 1 18 3 5 3 2 1 5 1 2 Destination IP Address Configuration Manager gt Protocols gt IP gt Static Routes None Any valid IP network address Specifies the IP address of the network to which you want to configure the static route Specifies a supernet for which you want to configure a black hole static route Enter the destination IP address in dotted decimal notation To configure a default route enter 0 0 0 0 To configure a black hole static route enter a supernet address You can configure up to 12 static routes to the same destination 1 3 6 1 4 1 18 3 5 3 2 1 5 1 3 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Address Mask Configuration Manager gt Protocols gt IP gt Static Routes None Based on the network class of the IP address you specified
128. back Network Mask 255 255 224 0 Match match Criteria range outbound peer 1 1 1 1 Outbound Peers 1 1 1 1 5 neighbor 1 1 1 1 route map ip bgp Protocols gt IP gt Policy Filters gt IncomingMap in foute map IncomingMap permit 10 match as path 5 set local preference 125 lp as path access list 5 permit 333_ 444 345 accept IncomingMap action accept match as path pattern 333 444 345 back peer 1 1 1 1 back back modify local preference 125 BGP 4 gt Accept Policies gt Add Name IncomingMap Action ACCEPT AS Pattern 333 444 345 Local Preference 125 Peer Address 1 1 1 1 continued 308628 14 00 Rev 00 Translating Cisco to Nortel Networks Equivalents Table C 1 Cisco to Nortel Networks BGP Translation continued Item Cisco Configuration Text BCC Command Site Manager Logical Steps 6 neighbor 1 1 1 1 route map ip bgp Protocols gt IP gt Policy Filters gt BGP 4 gt setASPath out announce setASPath Announce Policies gt Add foute map setASPath action announce modify Name setASPath permit 10 as path prepend 123 123 Action ANNOUNCE set as path prepend 123 back Replace As Path 123 123 123 match outbound peer 1 1 1 1 Peer Address 1 1 1 1 7 neighbor 1 1 1 1 route map ip bgp Protocols gt IP gt Policy Filters gt BGP 4 gt AdvertiseMap out announce AdvertiseMap Announce Policies gt Add foute map action announce Name AdvertiseMap AdvertiseMap permit 10 precedence 2 match Action ANN
129. ble C 5 summarizes the symbols used in Nortel Networks AS_Path pattern matching Table C 5 Nortel Networks AS_ Path Pattern Matching Symbols Symbol or Operator Meaning lt Denotes beginning of an AS SEQUENCE segment gt Denotes end of an AS SEQUENCE segment Denotes beginning of an AS SET segment Denotes end of an AS SET segment period Matches any single character including white space lt seq gt set Denotes an AS path containing a sequence in the first segment and a set in the second segment Denotes the preceding pattern occurs at the end of the AS path Logical OR match this of that Match exactly AS X Match AS pattern beginning with X for example _99 matches 99 991 9934 Match AS pattern ending with X for example 99_ matches 99 199 23299 308628 14 00 Rev 00 A acquisition mode for EGP neighbors 10 12 Acquisition Mode parameter 10 12 A 26 acronyms xviii Addr Mask Reply parameter A 32 Address Mask parameter 4 13 A 52 Address Resolution Type parameter A 33 address mask reply AMR IP configuration parameter A 32 Adjacent Host Address parameter A 54 Adjacent Host X 121 Address parameter A 56 A 57 advertise time command 6 9 aggregate route definition 1 4 AMR IP configuration parameter A 32 ARP Forwarding parameter A 45 ARP Server ATM Address Network Prefix parameter
130. ce Configuration Manager gt Protocols gt IP gt Global Drop Drop Drop and Log Determines what happens when IP encounters an invalid ARP source address If this parameter is set to Drop and Log IP logs an invalid ARP source address when processing an ARP request If this parameter is set to Drop IP does not log the invalid ARP source address In either case IP drops the invalid ARP request If you want to log the invalid ARP source address set the parameter to Drop and Log Otherwise set the parameter to Drop 1 3 6 1 4 1 18 3 5 3 1 1 4 308628 14 00 Rev 00 A 45 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Nonlocal ARP Destination Configuration Manager gt Protocols gt IP gt Global Drop Drop Accept Determines whether IP drops ARP requests in which the source and destination addresses are located in different networks or subnetworks This parameter allows Proxy ARP to generate replies when the source and destination networks in the ARP request are different To process ARP requests with source and destination addresses from different networks set the parameter to Accept The Proxy parameter must be set to Enable for the router to generate ARP replies 1 3 6 1 4 1 18 3 5 3 1 1 5 Default TTL Configuration Manager gt Protocol
131. ce for policies that match the same route EGP 1 3 6 1 4 1 18 3 5 3 2 6 5 1 8 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 8 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 9 1 8 EGP Specific Accept Policy Parameters Parameter Path Default Options Function Instructions MIB Object ID Peer List Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies An empty list A list of IP addresses Specifies the IP addresses of one or more EGP peers This policy applies to EGP advertisements from the peers on this list Use the default empty list to indicate that this policy applies to EGP advertisements from any EGP peer 1 3 6 1 4 1 18 3 5 3 2 6 5 1 10 308628 14 00 Rev 00 B 7 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID AS List Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Accept Policies An empty list A list of autonomous system numbers Specifies one or more autonomous system numbers This policy applies to EGP advertisements from peers located in the autonomous systems on this list Use the default empty list to indicate that this policy applies to EGP advertisements from peers in any AS 1 3 6 1 4 1 18 3 5 3 2 6 5 1 11 Gateway List Configuration Manager gt Protocols gt
132. ced routes and if BGP is included as a route source Specify one or more AS numbers Use the default empty list to indicate that this policy applies to BGP advertisements from peers in any AS EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 20 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 20 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 20 B 40 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies Received BGP Next Hop Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies one or more IP addresses This policy applies to BGP advertisements whose Next Hop attribute matches an IP address on this list and applies only to BGP sourced routes and if BGP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to BGP advertisements with any Next Hop attribute EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 21 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 21 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 21 EGP Specific Announce Policy Parameters Parameter Path Default Options Function Instructions MIB Objec
133. cement Enter a number for the cutoff penalty value 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 4 B 20 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Reuse Threshold Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 750 1 to 20000 Specifies the minimum threshold for the route penalty value If the penalty value falls below the value you enter for this parameter BGP no longer suppresses the route The penalty value decreases over time based on the values you set for the Reachable Decay and Unreachable Decay parameters Enter a number for the reuse penalty value 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 5 Reachable Decay Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 5 1 to 45 minutes Specifies the amount of time in minutes before BGP decrements the penalty value of a reachable route by half BGP uses a half life decay algorithm to decrement the penalty value Enter a value for the half life decay for reachable routes 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 6 308628 14 00 Rev 00 B 21 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path De
134. ch autonomous system has a NIC assigned decimal number ID You must supply the AS ID for the local autonomous system the AS to which this router belongs There is no default for this parameter You can use Site Manager to supply the local AS number Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose EGP 4 Choose Global The EGP menu opens The Edit EGP Global Parameters window opens 5 Set the Local Autonomous System ID parameter Click on Help or see the parameter description on page A 24 6 Click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 10 7 Configuring IP Exterior Gateway Protocols BGP and EGP Configuring a Neighbor You define a neighbor to neighbor relationship by setting EGP neighbor parameters as described under the following topics Topic Page Specifying the Neighbor s Address 10 9 Specifying the Gateway Mode 10 10 Enabling and Disabling the Neighbor Relationship 10 11 Choosing the Acquisition Mode 10 12 Choosing the Poll Mode 10 13 Setting Neighbor Timers 10 14 10 8 308628 14 00 Rev 00 Specifying the Neighbor s Address Customizing EGP Services You define the neighbor to neighbor relationship by specifying the IP a
135. chable withdrawn Using the BCC Navigate to a BGP peer prompt and enter route echo lt siate gt state is one of the following enabled disabled default For example the following command causes BGP to echo a route as unreachable bgp route echo enabled bgp 6 16 308628 14 00 Rev 00 Using Site Manager Establishing a Peer to Peer Session Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens want to edit BGP peer parameters 6 Click on BGP Peers 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window Set the Peer Route Echo Switch parameter Click on Help or see the parameter description on page A 16 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Disabling and Reenabling Loop Detection By default BGP terminates a peer to peer session if it discovers a loop in the AS path You can use the BCC or Site Manager to disable and reenable loop detection Using the BCC Navigate to a BGP peer prompt and enter detect as loop lt state gt
136. changed after the number of minutes you specify BGP unsuppresses the route and sets the penalty value to 0 Enter the maximum amount of time in minutes that the status of a route can remain unchanged reachable or unreachable If the status of the route remains unchanged for the specified number of minutes BGP resets the penalty value and flap count to 0 If the route is currently suppressed BGP unsuppresses it 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 9 308628 14 00 Rev 00 B 23 Configuring IP Exterior Gateway Protocols BGP and EGP Common Announce Policy Parameters Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Enable Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Enable Enable Disable Enables or disables this policy Set to Disable to disable the policy EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 2 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 2 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 2 B 24 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies Name Configuration Manager gt Protocols gt
137. command line causes BGP to submit aggregate routes to the routing table as black hole routes IP drops packets for unknown destinations but does not return ICMP destination unreachable messages to the sender bgp black hole punching drop bgp 308628 14 00 Rev 00 5 19 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Black Hole Routes parameter Click on Help or see the parameter description on page A 7 6 Click on OK Site Manager returns you to the Configuration Manager window Disabling and Reenabling the BGP 4 MED Attribute By default BGP 4 considers the multiexit discriminator MED attribute in the route selection process see Table 1 2 on page 1 9 You can use the BCC or Site Manager to configure BGP 4 so that it disregards the MED attribute in the route selection process Using the BCC Navigate to the BGP prompt and enter med comparison lt siate gt state is one of the following enabled default disabled For example the following command causes BGP 4 to disregard the MED attribute in an update when selecting a route bgp med comparison disabled bgp 5 20
138. cribes the length of the mask associated with the network This allows for both supernet and subnet advertisement The supernet advertisement is what makes classless interdomain routing CIDR possible In addition BGP 4 supports BGP confederations and TCP MD5 message authentication This chapter covers the following topics Topic Page Peer to Peer Sessions 1 5 Stub and Multihomed Autonomous Systems 1 6 Interior BGP Routing 1 6 IBGP Route Reflector 1 7 Equal Cost Multipath 1 8 BGP Updates 1 8 BGP OSPF Interaction 1 10 BGP 4 Confederations 1 10 BGP 4 TCP MD5 Message Authentication 1 11 BGP Implementation Notes Jail Peer to Peer Sessions A BGP router employs a BGP speaker which is an entity within the router that transmits and receives BGP messages and acts upon them A BGP speaker forms a neighbor relationship with another BGP speaker by establishing a peer to peer session See Chapter 6 Establishing a Peer to Peer Session 308628 14 00 Rev 00 1 5 Configuring IP Exterior Gateway Protocols BGP and EGP Stub and Multihomed Autonomous Systems An autonomous system can include one or more BGP speakers that establish peer to peer sessions with BGP speakers in other autonomous systems to provide external route information for the networks within the AS An AS containing multiple BGP speakers is considered to be a multihomed AS An AS containing a single BGP
139. d address To configure this parameter for a multinet or multigroup configuration see Configuring SMDS 1 3 6 1 4 1 18 3 5 3 2 1 24 1 21 FRB Broadcast Configuration Manager gt Protocols gt IP gt Interfaces 0 Any decimal number Provides a broadcast address for this IP interface in a frame relay network If you enter a value for this parameter the frame relay switch rather than the router will broadcast the message This parameter is displayed only if this is a frame relay circuit Enter the broadcast address provided by the frame relay subscription agreement 1 3 6 1 4 1 18 3 5 3 2 1 24 1 22 A 38 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters FRM Cast 1 DLCI Configuration Manager gt Protocols gt IP gt Interfaces 0 Any decimal number Provides a multicast address for this IP interface that will send messages to all OSPF routers in a frame relay network If you enter a value for this parameter the frame relay switch rather than the router will send the message to all OSPF routers This parameter has meaning only if OSPF has been added to this interface Enter the multicast address for all OSPF routers as provided by the frame relay subscription agreement 1 3 6 1 4 1 18 3 5 3 2 1 24 1 23 FRM Cast 2 DLCI Configuration Manager
140. d create a pilot configuration file see Quick Starting Routers Configuring BayStack Remote Access or Connecting ASN Routers to a Network Make sure that you are running the latest version of Nortel Networks BayRS and Site Manager software For information about upgrading BayRS and Site Manager see the upgrading guide for your version of BayRS 308628 14 00 Rev 00 XV Configuring IP Exterior Gateway Protocols BGP and EGP Text Conventions This guide uses the following text conventions angle brackets lt gt bold text braces brackets ellipsis points Indicate that you choose the text to enter based on the description inside the brackets Do not type the brackets when entering the command Example If the command syntax is ping lt p_address gt you enter ping 192 32 10 12 Indicates command names and options and text that you need to enter Example Enter show ip alerts routes Example Use the dinfo command Indicate required elements in syntax descriptions where there is more than one option You must choose only one of the options Do not type the braces when entering the command Example If the command syntax is show ip alerts routes you must enter either show ip alerts or show ip routes but not both Indicate optional elements in syntax descriptions Do not type the brackets when entering the command Example If the command syntax is show ip int
141. ddress of the router that is to be the remote neighbor You can use Site Manager to supply the address of the remote neighbor Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose EGP The EGP menu opens Choose Neighbors The IP Interface List for EGP window opens Click on the IP interface for which you want to specify the neighbor s address Set the Remote Autonomous System IP Address parameter Click on Help or see the parameter description on page A 25 The parameter values for that interface appear in the window Click on Apply and then click on Done Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 10 9 Configuring IP Exterior Gateway Protocols BGP and EGP Specifying the Gateway Mode You can configure the EGP router to operate in one of two gateway modes for any given IP interface Noncore When the router is configured as a noncore gateway the AS to which it belongs acts as a stub AS It advertises and forwards only traffic that originated or is destined for a network within its AS Core When the router is configured as a core gateway the AS to which it belongs acts as a transit AS In the core mode it can advertise and forward traffic to networks that are reachable inside or outside
142. decctenctecninonendeedannedeunneneete 1 6 terior BUR ROUNO sous sce ncn tseis atlas aa aeiaai E EASE aana iaa a AAS E Eh 1 6 IBGP Route Reflector RA P Aaa Scie T ere meas ler roe Leroi NUNE generar ere peer eerer erect ree ree a Tre rrre tre rr ttr 1 8 G maa e ole kc saan eee ee ene e cr ne ee reennee aE 1 8 PORN UMULES sociso on a OA 1 9 BPS Te FAC GO icscen arcane eaten A A 1 10 BGP 4 Confederations sane E E E A aaa 1 10 BGP 4 TCP MDS Message AuthentcalON seccdisscescnccenicescvsuiertaversseradeindnmceieandoncs 1 11 BOF implementation PINGS sags cea ssi nals aaun aonni nana aa aai aaa aN 1 11 308628 14 00 Rev 00 V Chapter 2 Starting BGP Services with the BCC SSCA o a E E E E A E E A 2 1 Step 1 Configuring a Physical Interface issiskiria 2 1 Step 2 Configuring an IP Interface 06 PE FT iisti EE E 2 2 SO BGP oarra E A taauaNaae 2 3 Step 1 Configuring Global BGP iss cctiniscinnansmclased ines naeia a aiana 2 3 Step 2 Defining a Peer to Peer Connection esseeeseeesseesssssrseesssesssressnssssnessnnesnnses 2 3 Chapter 3 Starting BGP and EGP Services with Site Manager Starting IP and BGP ssscssccccticndessiess T stis E T ET riai re uo Deleting BGFP Tomiho MOUE wccijiisectsctiveetaente dis Matic sie ete D 3 3 Deleting BGP 3 and BGP 4 from the Router ccccccsseeeseseeeeeneeeeeaaeeeeeeeeteaeeeeeaeeeeaes 3 3 RSL ECAP E E E E A E E E E AE E 3 4 Delsing EGF Theme Te RONI
143. dundant routes For example the following command disables BGP redundancy checking allowing BGP to establish multiple TCP sessions on different physical connections with the same remote peer bgp redundant connection disabled bgp 5 10 308628 14 00 Rev 00 Configuring and Customizing BGP The following command sequence reenables redundancy checking and configures BGP to allow up to 50 redundant routes bgp redundant connection enabled bgp max redundant routes 50 bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Detect Redundant Connections parameter Click on Help or see the parameter description on page A 5 6 Click on OK Site Manager returns you to the Configuration Manager window Enabling Multihop Connections By default BGP enforces the one hop rule for BGP peers the remote peer must be located on a directly attached network You can use the BCC or Site Manager to override the restriction and allow multihop connections Caution Enabling multihop BGP connections is dangerous because it can cause BGP speakers to establish a BGP connection that traverses a third party AS which may violate policy considerations
144. e Source OSPF STATIC protocol source ospf static 15 timers bgp 60 180 ip bgp Protocols gt IP gt BGP gt Peers peer 1 1 1 1 1 1 1 2 BGP Peers as 333 Keepalive Timer 60 keepalive 60 Holdtime 180 holddown 180 16 interface loopbackO virtual ip 1 1 1 1 255 255 255 255 Protocols gt IP gt Circuitless IP gt Create ip address 1 1 1 1 IP Address 1 1 1 1 255 255 255 255 Subnet Mask 255 255 255 255 17 ip subnet zero ip all subnets enabled Protocols gt IP gt Global Zero Subnet Enable 18 router bgp 4001 ip bgp Protocols gt IP gt BGP gt BGP Global Bgp confederation local as 5 BGP Local AS 5 identifier 5 confederation id 4001 Confederation ID 4001 bgp confederation peers confederation peers 4002 4003 Confederation Peer gt List 4002 4003 4004 4004 Autonomous System 4002 4003 neighbor 1 2 3 4 peer 1 2 3 1 1 2 3 4 as 4002 4004 remote as 4002 peer 3 4 5 1 3 4 5 6 as 510 neighbor 3 4 5 6 remote as 510 19 router bgp 1000 ip bgp Protocols gt IP gt BGP gt Peers neighbor 132 245 10 2 local as 1000 Local AS 1000 password bla4u00 2nkq peer 132 245 10 1 132 245 10 2 as 1000 tcp authentication md5 tcp md5 key bla4u00 2nkq Peer Address 132 245 10 2 Peer AS 1000 Local Address 132 245 10 1 Tcp Authentication MD5 TcpMd5Key bla4u00 2nkq 308628 14 00 Rev 00 C 5 Configuring IP Exterior Gateway Protocols BGP and EGP Interpreting the Cisco to Nortel Networks BGP Translation Table The numbers in the following list corr
145. e external route source identifiers If you specify an external route source a route from that source that meets the other criteria of this policy matches the policy This parameter applies only to OSPF routes that use the ASE type 2 metric The protocol from which OSPF received the route is encoded in the ASE metric along with the route s metric To specify any external route source use the default ospf type protocol source any default type 1 type 2 external internal any default direct static rip ospf egp bgp Specifies which types of OSPF routes match this policy and applies only to OSPF sourced routes and if OSPF is included as a route source Specifies one or more route source identifiers If you select a route source ID a route from that source that meets the other criteria of this policy matches the policy bgp as List of AS numbers Specifies a list of autonomous system numbers This policy applies to BGP advertisements received from BGP peers in this AS and applies only to BGP sourced routes and if BGP is included as a route source continued 308628 14 00 Rev 00 7 19 Configuring IP Exterior Gateway Protocols BGP and EGP Table 7 6 BCC Match Criteria for BGP Announce Policies continued Criterion Values Function bgp next hop List of IP Specifies one or more IP addresses This addresses policy applies to BGP advertisements whose Next Hop
146. e intra AS IBGP routing 308628 14 00 Rev 00 1 11 Configuring IP Exterior Gateway Protocols BGP and EGP If OSPF is the IGP you should also use the default OSPF tag construction Using EGP or modifying the OSPF tags makes network administration and proper construction of BGP path attributes more difficult e For any router supporting both BGP and OSPF the OSPF router ID and the BGP identifier must be the same For information about configuring OSPF see Configuring IP ARP RARP RIP and OSPF Services 1 12 308628 14 00 Rev 00 Chapter 2 Starting BGP Services with the BCC This chapter describes how to use the BCC to start the following services with a basic configuration that is a configuration using all available default values Topic Page Starting IP 2 1 Starting BGP 2 3 Starting IP To start IP on the router you must 1 Configure a physical interface on an available slot connector 2 Configure an IP interface on the physical interface Step 1 Configuring a Physical Interface To configure a physical interface on a slot and connector navigate to the top level box prompt and enter lt interface_type gt slot lt slot_number gt connector lt connector_number gt interface_type is the name of a link module on the router slot_number is the number of the slot on which the link module is located connector_number is the number of a connector on the link module 308628 14
147. ecord in the IP routing tables Select disable to make the static route record inactive in the IP routing table the IP router will not consider this static route Select enable to make the static route record active again in the IP routing table address The destination IP Specifies the IP address of the network to address you supplied which you want to configure the static route when you configured Enter the destination IP address in the static route You dotted decimal notation To configure a cannot modify this default route enter 0 0 0 0 To configure a address black hole static route enter a supernet address You can configure up to 12 static routes to the same destination mask The destination IP Specifies the subnet mask of the address mask you supplied when you configured the static route You cannot modify this address mask destination network Enter the subnet or supernet mask in dotted decimal notation To configure a default route enter 0 0 0 0 To configure a black hole static route enter a supernet mask next hop address The next hop IP address mask you supplied when you configured the static route You cannot modify this address mask Specifies the IP address of the next hop router Enter the IP address in dotted decimal notation To configure a black hole static route enter 255 255 255 255 If you are configuring a static route to an unnumbered interface enter 0 0 0 0 next hop mask
148. eerTcpMd5 Key and wfBgpPeerTcpMd5KeyStorage TCP monitors the authentication using the attribute wfTcpConnMd5Errors in the wfTcpConnEntry record Initializing TCP with the MD5 Option If an MDS authentication key is configured for a BGP peer that has BGP authentication enabled then BGP reads the authentication key from the MIB decrypts it if necessary and passes the unencrypted authentication key to TCP If there is no NPK available to decrypt an encrypted authentication key BGP logs an event BGP TCP MD5 NPK No NPK configured If TCP receives an MD5 authentication key it reduces its Maximum Segment Size MSS by 18 octets the length of the TCP MDS option It also adds an MDS signature to each transmitted packet Generating MD5 Signatures on Transmitted BGP TCP Packets A BGP peer calculates the MDS signature for a BGP message on the following elements e TCP pseudo header e TCP header excluding options e TCP segment data e TCP MDS authentication key The peer inserts the resulting 16 byte MDS signature into the following TCP options kind 19 length 18 308628 14 00 Rev 00 5 23 Configuring IP Exterior Gateway Protocols BGP and EGP Verifying MD5 Signatures on Received BGP TCP Packets When TCP receives a packet it checks whether the connection has been configured for authentication If it has TCP verifies that the packet contains a kind 19 option If the packet does not contain that option then TCP logs a TCP MDS
149. eers 15 seconds A value greater than 0 Determines the minimum amount of time that must elapse between successive advertisements of update messages that report changes within the advertising BGP speaker s own autonomous system Enter a value greater than 0 seconds 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 30 Local AS to Advertise to Peer Configuration Manager gt Protocols gt IP gt BGP gt Peers Null 1 to 65535 Specifies the AS number that is sent in an open message to this peer Enter an AS number To specify the AS number you set with the BGP Local AS parameter use the default null 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 31 Peer Max Update Size Configuration Manager gt Protocols gt IP gt BGP gt Peers 800 bytes 64 to 4096 Specifies the maximum size in bytes of update messages that are sent to this peer Use the default or specify a size Note that if the size of the update message that advertises a single route is greater than the configured message size the actual message size can exceed the configured value 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 32 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Peer Route Echo Switch Configuration Manager gt Protocols gt IP gt BGP gt Peers Enable Enable Disable Contro
150. enabling IBGP Support c ccceseeeeceeeeeeeeeeeeeeeeeeeeeeeeeaeeeeneenites 5 6 Specifying Route Types for IBGP Advertisements T PER Toan Pe Setting the Update Interval TIMET aariarreicreseriiuiirriiini arpit nN nnn ENA 5 9 Allowing Redundant Connections ssssrississuisnnsssresnaeia aa 5 10 Enabling Multihop Connections acd cost iccecctcnaty cede sceyaceeenctid aac naan aaa 5 11 Disabling and Reenabling Dynamic Policy Configuration esseeeseeesseeeseeeneeee 5 13 Configuring BGP as a Soloist sa eee EE E ET pies met 5 14 Associating a Route Reflector with a Cluster ID o eceeseeeeeeeeeeeeeeeneeeeeeeeeeeeees 5 15 Disabling and Reenabling Route Aggregation cccccescceeseeeeeceeeeeeeeeeeeeeeteeesaes 5 15 Configuring BGP 4 Confederations E T T T boetan ecaa ers Enabling and Disabling Black Hole PUNCHING cceeeecceceeeseeeeeeeeneeeeeeeeneeneees 5 18 Disabling and Reenabling the BGP 4 MED Attribute oo cece eee ceeeteeeeteeeeeeaes 5 20 Configuring and Enabling MD5 Authentication ccccccssseeeeesssneeeeeessneeeeenees 5 21 Entering and Storing MD5 Authentication Keys cccsccccessseeeeeeeseeeeeessneeeeeees 5 22 Configuring BGP Authentication Mei era iratai aoas A E 5 23 Initializing TOP with the MDS Opty sisirain ennnen 5 23 Generating MD5 Signatures on Transmitted BGP TCP Packets ceeee 5 23 Verifying MD5 Signatures on Received BGP TC
151. er 1 Exterior Gateway Protocols BGP EGP The following topics introduce concepts and terminology used in this guide Topic Page What Gateway Protocols Do 1 1 Border Gateway Protocol BGP 13 Exterior Gateway Protocol EGP 1 3 Classless Interdomain Routing 1 4 What Gateway Protocols Do LANs and WANs interconnected by IP routers form a group of networks called an internet For administrative purposes an internet is divided into routing domains called autonomous systems An autonomous system AS is simply a collection of routers called gateways in IP terminology and hosts Each autonomous system has its own unique AS number assigned by the appropriate Network Information Center entity Figure 1 1 depicts a sample internet segmented into three autonomous systems 308628 14 00 Rev 00 1 1 Configuring IP Exterior Gateway Protocols BGP and EGP Router 2 Autonomous LAN system 2 B Coane Router a 1 Autonomous system 3 Router Router Autonomous 8 7 system 1 Router 6
152. er the message encryption key node protection key NPK MEK value before setting the MD5 authentication parameters For information on Technician Interface secure shell see Configuring IPsec Services For information on DES WEP and NPK see Configuring Data Encryption Services You can enter the authentication keys through Site Manager or the BCC 5 24 308628 14 00 Rev 00 Configuring and Customizing BGP Using the BCC To set the BGP 4 authentication parameters navigate to the peer prompt and enter tcp authentication lt siate gt state is one of the following none default md5 For example the following command enables BGP 4 MD5 authentication bgp tcp authentication md5 bgp If TCP authentication is not enabled the other BGP authentication parameters are irrelevant If you have specified MD5 authentication you can continue configuring the BGP 4 authentication parameters At the peer prompt enter tcp md5 key lt key gt key is the value that you assign to the MDS key There is no default value For example the following command sets the BGP 4 MDS key to corpkey bgp tcep md5 key corpkey bgp You can also specify whether to store the key as clear text or encrypted At the peer prompt enter tcp md5 key storage lt format gt format is one of the following clear text default encrypted For example the following command sets the BGP 4 MDS key storage format to encrypted bgp tcep md5 key e
153. erface 2 You can use the BCC or Site Manager to configure EBGP ECMP for route balance and traffic load balance Using the BCC Navigate to the BGP prompt and choose a peer to modify Enter ebgp ecmp method lt methoad gt method is one of the values shown in Table 9 2 308628 14 00 Rev 00 9 7 Configuring IP Exterior Gateway Protocols BGP and EGP Table 9 2 EBGP ECMP Methods Method Meaning route balance BGP submits one BGP route to the IP routing table for each BGP destination using in turn round robin the available ECMP routes to the next hop traffic balance BGP submits multiple routes to IP using all known IGP ECMP IP next hops For example the following sequence of BCC commands 1 Configures an IP circuitless interface 201 1 1 1 on the local router s virtual circuit 2 Configures two static routes to destination 201 1 1 4 the IP circuitless interface on the remote router Assigns router ID 201 1 1 1 to BGP on the local router Associates local BGP with AS 11 Configures local BGP for multihop peer to peer sessions DN as ee TO Establishes a BGP peer to peer session between virtual interface 201 1 1 1 on the local router and virtual interface 201 1 1 4 on the remote router 7 Configures the peer to peer session for route balancing box Virtual virtual ip 201 1 1 1 30 ip 201 1 1 1 255 255 0 252 box box ip ip static route 201 1 1 4 30 198 2 1 1 static route 201
154. erfaces alerts you can enter either show ip interfaces or show ip interfaces alerts Indicate that you repeat the last element of the command as needed Example If the command syntax is ethernet 2 1 lt parameter gt lt value gt you enter ethernet 2 1 and as many parameter value pairs as needed xvi 308628 14 00 Rev 00 italic text screen text separator gt vertical line Preface Indicates file and directory names new terms book titles and variables in command syntax descriptions Where a variable is two or more words the words are connected by an underscore Example If the command syntax is show at lt valid_route gt valid_route is one variable and you substitute one value for it Indicates system output for example prompts and system messages Example set Trap Monitor Filters Shows menu paths Example Protocols gt IP identifies the IP option on the Protocols menu Separates choices for command keywords and arguments Enter only one of the choices Do not type the vertical line when entering the command Example If the command syntax is show ip alerts routes you enter either show ip alerts or show ip routes but not both 308628 14 00 Rev 00 xvii Configuring IP Exterior Gateway Protocols BGP and EGP Acronyms This guide uses the following acronyms ARP AS ATM BGP BootP CIDR DES DLCI ECMP EGP FDDI IBGP ICMP IGP IP LAN
155. ernal For example the following command sequence defines a peer to peer session between two route reflectors represented by addresses 2 2 2 2 and 2 2 2 3 located in different clusters in AS 2 ip bgp bgp peer local 2 2 2 2 remote 2 2 2 3 as 2 peer 2 2 2 2 2 2 2 3 peer mode reflector external peer 2 2 2 2 2 2 2 3 308628 14 00 Rev 00 8 7 Using Site Manager Configuring IP Exterior Gateway Protocols BGP and EGP To establish a peer to peer session with a route reflector in another cluster complete the following tasks Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on Add 8 Set the following parameters Peer Address Peer AS e Local Address e Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 The BGP Peer Parameters window opens 9 Click on OK Site Manager returns you to the BGP Peer List window 10 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 Confi
156. ertised for a originating network matching this policy and if advertised what value to use Select None to indicate that no value is to be advertised Select Specified to indicate that the value you specify for the Multi Exit Discriminator Value parameter is to be used Select Originating to indicate that the metric from the originating protocol is to be used This parameter is valid only if the Action parameter is set to Propagate med null default ora Specifies a metric for the multiexit discriminator metric value attribute next hop null default or an Overrides the next hop path attribute with the ip address IP address you specify origin as is default Specifies an origin attribute override The Origin attribute of a route matching this policy will be replaced with the indicated value community method as is default remove append replace Specifies the action to take on the BGP communities attribute in updates matching this policy continued 308628 14 00 Rev 00 7 15 Configuring IP Exterior Gateway Protocols BGP and EGP Table 7 5 BCC BGP Announce Policy Parameter Overrides continued Parameter Values Function advertise List of IP Specifies a list of networks that BGP advertises addresses instead of the networks in the routing table community List of Specifies a list of communities that BGP communities advertises The BCC treats this parameter as a
157. es log eBGP p 15 debug ip bgp events show bgp errors 16 show ip route show ip routes 17 trace 1 1 1 1 ping p 1 1 1 1 C 8 308628 14 00 Rev 00 Translating Cisco to Nortel Networks Equivalents Interpreting the Cisco and Nortel Networks BGP Operational Table The following list describes the function of the Cisco and Nortel Networks BCC operational commands in the corresponding row of Table C 2 1 10 11 12 13 14 15 16 Do not synchronize between BGP and IGP this enables a router to advertise a BGP network to an external peer without having that network exist in the IP routing table Route reflection is a method to alleviate the need for full mesh IBGP by allowing an internal BGP speaker to reflect or re advertise routes learned through an IBGP connection to another IBGP peer Minimize the instability caused by route flapping Confederations are used to reduce the number of peers in an AS by breaking the network into multiple smaller ASs The Collision Detection feature if disabled allows redundant BGP connections to the same router Show BGP routing table Show status of BGP peers Show the router s BGP timers Within Cisco s show ip bgp neighbor command the keepalive holddown and external advertisement timers are displayed Display the router s announce policies Cisco s show ip bgp neighbor command displays the router s incoming and outgoing route filters Show BGP route
158. espond to the item numbers in Table C 1 Each numbered item in this list describes the function of the commands in the corresponding row of that table 1 Enable the Border Gateway Protocol BGP routing process and identify the local router autonomous system AS 333 Activate a BGP session with peer router IP address 1 1 1 2 which belongs to AS 444 If the local and remote AS numbers are the same the BGP session is internal otherwise it is an external BGP session Note that Nortel Networks also requires definition of the local router IP address 1 1 1 1 and Local Address which are the same Advertise network 1 1 1 0 mask 255 255 255 0 and originate it from my AS Note that network 1 1 1 0 must be present in the IP routing table for Cisco s BGP network command to advertise the route Accept incoming advertisement of network 128 1 0 0 mask 255 255 0 0 from peer IP address 1 1 1 1 as specified by Cisco access list 5 or Nortel Networks policy name IncomingRoutes Announce advertisement of network 195 89 32 0 mask 255 255 224 0 to peer IP address 1 1 1 1 as specified by Cisco access list 10 or Nortel Networks policy name OutgoingRoutes Accept incoming advertisements from peer 1 1 1 1 match on AS Path that contain either AS 333 444 or 345 and set Local Preference to 125 as specified by Cisco route map and Nortel Networks policy name IncomingMap Announce advertisements to peer 1 1 1 1 and append AS Path lt 123 12
159. esponding natural network routes for advertisement to BGP peers You can use Site Manager or the BCC to disable this feature This switch does not affect the advertisement of BGP originated routes 308628 14 00 Rev 00 5 15 Configuring IP Exterior Gateway Protocols BGP and EGP Using the BCC Navigate to the BGP prompt and enter subnet aggregation lt state gt state is one of the following enabled default disabled For example the following BCC command disables subnet aggregation bgp subnet aggregation disabled bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Aggregate Subnets parameter Click on Help or see the parameter description on page A 7 6 Click on OK Site Manager returns you to the Configuration Manager window 5 16 308628 14 00 Rev 00 Configuring and Customizing BGP Configuring BGP 4 Confederations If this router is a member of an autonomous system that is part of a confederation you can configure the confederation ID for this router You can also specify the list of this BGP speaker s peers in other sub ASs within the same confederation If the confederation identifier is not available nil this
160. eters Peer Address Peer AS Local Address Peer Mode Click on Help or see the parameter descriptions beginning on page A 10 7 Click on OK Site Manager enables default BGP service For information about unnumbered interfaces see Configuring an Unnumbered IP Interface on page 3 7 You customize IP and BGP by modifying IP parameters For information see Chapter 4 Configuring and Customizing IP for BGP 3 2 308628 14 00 Rev 00 Starting BGP and EGP Services with Site Manager Deleting BGP from the Router You can delete BGP from all router circuits on which it is currently enabled To delete BGP complete the following steps Site Manager Procedure 1 You do this In the Configuration Manager window choose Protocols System responds The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Delete BGP Click on OK Site Manager opens a window prompting Do you really want to delete BGP Site Manager removes BGP from all circuits on the router and returns you to the Configuration Manager window Deleting BGP 3 and BGP 4 from the Router You can delete BGP 3 and BGP 4 from all router circuits on which they are currently enabled To delete BGP 3 complete the following steps Site Manager Procedure You do this System responds 1 In the Configuration Manager w
161. etric value to be used to compare this policy with other policies that a route may match A policy with a higher metric takes precedence over a policy with a lower metric In case of a tie the protocol uses an internal index value assigned to the policy by IP software In general the index value is indicated by the position of the policy in the Site Manager display the last policy in the display has the highest index value Use this parameter to assign precedence to policies that match the same route EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 7 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 7 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 7 B 28 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies Route Source Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Any Any Direct Static RIP OSPF EGP BGP Specifies one or more route source identifiers If you select a route source ID a route from that source that meets the other criteria of this policy matches the policy To specify any source use the default EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 8 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 8
162. example C1 617 555 5000 FFFF Specifies a MAC media access control address for this IP interface The IP router will use its IP address and this MAC address when transmitting and receiving packets on this interface Enter 0 to configure the IP router to use its IP address and the circuit s MAC address when transmitting packets on this interface Enter your own MAC address to configure the IP router to use its IP address and the specified MAC address when transmitting packets on this interface If the interface is on an SMDS circuit by default IP uses the SMDS configured address To configure this parameter for a multinet or multigroup configuration see Configuring SMDS 1 3 6 1 4 1 18 3 5 3 2 1 24 1 10 308628 14 00 Rev 00 A 35 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID TR Endstation Configuration Manager gt Protocols gt IP gt Interfaces Off On Off Specifies source routing over token ring selection Use the On option to enable the parameter 1 3 6 1 4 1 18 3 5 3 2 1 24 1 19 Redirect Configuration Manager gt Protocols gt IP gt Interfaces Enable Enable Disable Indicates whether this interface sends out ICMP redirects ICMP redirects are messages sent by the router to alert a host that it should be using a different pat
163. ext Hop Self Configuration Manager gt Protocols gt IP gt BGP gt Peers Disable Enable Disable Enables or disables the use of third party advertisements Specify Enable to send the local peer s address as the next hop in all advertisements Accept the default Disable to allow third party advertisements 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 40 Peer EBGP ECMP Method Configuration Manager gt Protocols gt IP gt BGP gt Peers Disabled Disabled Route Balance Traffic Balance Configures BGP to use ECMP routes in the routing table for route balancing or traffic load balancing To configure BGP to use ECMP routes for route balancing set this parameter to Route Balance To configure BGP to use ECMP routes for traffic load balancing set this parameter to Traffic Balance 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 42 Tcp Authentication Configuration Manager gt Protocols gt IP gt BGP gt Peers None None MD5 Specifies whether to use MD5 authentication for this connection Specify MD5 to enable BGP TCP MD5 authentication for this connection This also makes Tcp Md5 Key Storage and Tcp Md5 Key parameters accessible Accept the default None to disable BGP TCP MD5 authentication for this connection 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 45 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Pat
164. faces e Disables IP forwarding caches By default IP maintains a forwarding cache on each IP interface IP maintains this table as a cache for routes that are frequently used to forward data packets that arrive on the interface However if the number of frequently used routes exceeds the size of the forwarding table the router continually updates the forwarding cache by removing old routes and installing new route entries ISP mode disables all forwarding caches on all IP interfaces and optimizes the routing table to allow direct forwarding avoiding the overhead of cache misses and cache updates If you choose ISP mode you do not have to explicitly disable the forwarding tables on each interface 308628 14 00 Rev 00 4 7 Configuring IP Exterior Gateway Protocols BGP and EGP The following parameter settings also help to optimize router performance and operation IP Parameter Setting Route Filter Support Disabled Maximum Policy Rules Set as required Estimated Networks Set as required Redirect Disabled at router interconnection points By default ISP mode features are disabled on the router You can use the BCC or Site Manager to enable and disable ISP mode as required Using the BCC Navigate to the IP global prompt and enter isp mode lt state gt state is one of the following enabled disabled default Using Site Manager Site Manager Procedure You do thi
165. fault Options Function Instructions MIB Object ID Unreachable Decay Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 15 1 to 45 minutes Specifies the amount of time in minutes before BGP decrements the penalty value of an unreachable route by half BGP uses a half life decay algorithm to decrement the penalty value Enter a value for the half life decay for an unreachable route 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 7 Max HoldDown Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 45 1 to 60 minutes Specifies the maximum amount of time that a route can remain suppressed If the route remains suppressed after the number of minutes you specify BGP unsuppresses it even if the penalty value exceeds the threshold Enter the maximum amount of time in minutes that the route should be suppressed 1 3 6 1 4 1 18 3 5 3 2 5 1 8 1 8 B 22 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Memory Limit Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies gt Route Flap 45 1 to 60 minutes Specifies the maximum amount of time that the status of a route can remain unchanged reachable or unreachable before BGP unsuppresses the route If the status of the route remains un
166. figuration Manager window 308628 14 00 Rev 00 Appendix A Site Manager Parameters This appendix describes the Site Manager parameters relevant to BGP and EGP Topic Page BGP Parameters A 1 EGP Parameter A 24 IP Parameters A 28 BGP Parameters Topic Page BGP Configuration Parameters A 2 BGP Global Parameters A 2 BGP 3 Global Parameter A 10 BGP 4 Global Parameter A 10 BGP Peer Parameters A 1 BGP AS Weight and Weight Class Parameters A 19 BGP Event Message Parameters A 22 308628 14 00 Rev 00 A 1 Configuring IP Exterior Gateway Protocols BGP and EGP BGP Configuration Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Identifier Choose BGP in the Select protocols window None An IP address of an IP interface on this router Identifies the BGP router There is no default for this parameter You must use an IP address of one of the router s IP interfaces Either accept the current BGP identifier or enter a new IP address The BGP identifier must be one of the router s IP interfaces If both BGP and OSPF are running on the router then the OSPF router ID must be equivalent to one of the configured IP interfaces 1 3 6 1 4 1 18 3 5 3 2 5 1 1 4 Local AS Select BGP in the Select protocols window None
167. forces the rule that requires an external BGP peer to be located on a directly attached network Use this parameter to override the restriction Enabling multihop BGP connections is dangerous because it can cause BGP speakers to establish BGP connections that traverse a third party AS possibly violating policy considerations and introducing forwarding loops 1 3 6 1 4 1 18 3 5 3 2 5 1 1 6 308628 14 00 Rev 00 A 5 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID BGP Dynamic Policy Change Support Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Specifies whether BGP dynamically reevaluates all routes affected by a policy when you modify the policy Select disable if you want BGP to restart all connections when you modify a policy 1 3 6 1 4 1 18 3 5 3 2 5 1 1 19 BGP Soloist Slots Configuration Manager gt Protocols gt IP gt BGP gt BGP Global All slots Slots 1 to 14 Specifies slots on which the BGP soloist is eligible to run Accept the default all slots to enable BGP to run on all slots To configure BGP to run as a soloist on a particular slot specify the slot number 1 3 6 1 4 1 18 3 5 3 2 5 1 1 20 Cluster Iden
168. gin Replace As Path Local Preference Override Local Preference Value Next Hop Atomic As Pattern BGP Community to announce BGP Community attribute action BGP Community to match As Prepend Click on Help or see the parameter descriptions beginning on page B 3 8 Click on OK Site Manager returns you to the BGP4 Announce Policy Filters window 308628 14 00 Rev 00 7 13 Configuring IP Exterior Gateway Protocols BGP and EGP Supplying Modification Values for a BGP Announce Policy You can use the BCC or Site Manager to supply values that BGP uses to modify fields in a BGP update that matches the policy Using the BCC Navigate to the policy specific prompt and enter modify For example the following command invokes a modification prompt for BGP announce policy pol_1 announce pol_1 bgp modify modify bgp announce pol_1 To supply a value enter lt parameter gt lt value gt parameter value is one of the combinations shown in Table 7 5 Table 7 5 BCC BGP Announce Policy Parameter Overrides Parameter as path Values Function null default or an Specifies an AS path that overrides the AS path AS path attribute of a route matching this policy An AS path is composed of AS path segments Each path segment includes a path segment type a path segment length specifying the number of ASs in the segment and a path segment value containing one or more AS numbe
169. gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the IP address of one or more EGP peers This policy applies to EGP advertisements authored by a router on this list and applies only to EGP source routes and if EGP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to EGP advertisements from any router EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 16 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 16 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 16 B 36 308628 14 00 Rev 00 Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Routing Policies From EGP AS Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of autonomous system numbers Specifies one or more autonomous system numbers This policy applies to EGP advertisements received from EGP peers in an AS on this list and applies only to EGP sourced routes and if EGP is included as a route source Specify one or more AS numbers Use the default empty list to indicate that this policy applies to EGP advertisements from peers in any AS EGP 1 3 6 1 4 1 18
170. gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 1 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Weight Value 2 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 2 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 Weight Value 3 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 3 weight value to
171. gt Protocols gt IP gt Interfaces 0 Any decimal number Provides a multicast address for this IP interface that will send messages to all OSPF designated routers in a frame relay network If you enter a value for this parameter the frame relay switch rather than the router will send the message to all OSPF designated routers This parameter has meaning only if OSPF has been added to this interface Enter the multicast address for all OSPF designated routers as provided by the frame relay subscription agreement 1 3 6 1 4 1 18 3 5 3 2 1 24 1 24 308628 14 00 Rev 00 A 39 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Slot Mask Configuration Manager gt Protocols gt IP gt Interfaces Slot mask bit set to 1 enabling circuitless IP interface support for every router slot running IP For each slot in the router Site Manager allows you to set the slot mask bit to 1 circuitless IP interface support enabled or O circuitless IP interface support disabled Specifies whether circuitless IP interface support is enabled or disabled on each slot in the router If you configured a circuitless IP interface and do not want it to run on certain slots set the slot mask bit to 0 on those slots Be certain to keep the slot mask bit set to 1 on at least one slot running IP otherwise the circuitless IP interface will not initia
172. gt IP gt Policy Filters gt BGP 4 gt 10 out lp as path access list 10 deny 350_400_500 ip as path access list 10 permit 350_40 announce DenyAS action ignore precedence 2 match as path pattern 350 400 500 outbound peer 1 1 1 1 ip bgp announce AllowAS action announce T precedence 1 match as path pattern 350 400 outbound peer 1 1 1 1 Announce Policies gt Add Name DenyAS Action IGNORE AS Pattern 350 400 500 Rule Precedence 2 Peer Address 1 1 1 1 Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies gt Add Name AllowAS Action ANNOUNCE AS Pattern 350 400 Rule Precedence 1 Peer Address 1 1 1 1 neighbor MyPeers peer group neighbor MyPeers remote as 333 neighbor MyPeers route map AdvertiseMap out neighbor MyPeers route map FilterMap in neighbor 1 1 1 1 peer group MyPeers neighbor 2 2 2 2 peer group MyPeers 11 aggregate address 195 89 8 0 255 255 248 0 ip bgp announce AdvertiseMap action announce match outbound peer 1 1 1 1 back N outbound peer 2 2 2 2 back outbound as 333 ip bgp accept FilterMap action accept match peer 1 1 1 1 back peer 2 2 2 2 back as 333 ip bgp announce AggregateNets action announce match network 195 89 8 0 255 255 248 0 range back back modify advertise 195 89 8 0 255 255 248 0 back advertise 255 255 255 255 255 255 255 255 Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies gt Add Name AdvertiseMap
173. guring a Route Reflector To associate a route reflector with a cluster complete the following tasks Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the Cluster Identifier parameter Click on Help or see the parameter description on page A 6 6 Click on OK Site Manager returns you to the Configuration Manager window Configuring an RR Client An RR client is a BGP IBGP speaker with a peer to peer session with a route reflector and one or more peer to peer sessions with external BGP speakers You can use the BCC or Site Manager to establish a peer to peer session with one or more route reflectors in the same cluster Using the BCC Navigate to the global BGP prompt and enter peer local lt client_address gt remote lt reflector_address gt as lt as_number gt client_address is the IP address of an interface on the local client reflector_address is the IP address of an interface on the remote reflector as_number is an integer identifying the AS in which the client and the server are located 308628 14 00 Rev 00 8 9 Configuring IP Exterior Gateway Protocols BGP and EGP When the session specific prompt appears enter the following command peer mode none
174. h Default Options Function Instructions MIB Object ID Tcp Md5 Key Storage Configuration Manager gt Protocols gt IP gt BGP gt Peers None if TCP Authentication is None Clear Text if TCP Authentication is MDS Clear Text Encrypted Specifies whether the MD5 authentication key is stored as clear text or encrypted Accept the default value Clear Text to specify no encryption for the stored key Set this parameter to Encrypted to store the MDS key in encrypted form Setting this parameter to Encrypted also makes the NPK parameter visible 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 46 Node Protection Key Configuration Manager gt Protocols gt IP gt BGP gt Peers An 8 byte value If TCP Authentication is MD5 and Tcp Md5 Key Storage is Encrypted this value is the one configured as the node protection key in the wf_key_file_path environment variable Not used if TCP Authentication is None ASCII character string Used as a cryptographic key for protecting sensitive MIB objects The NPK value is stored in nonvolatile memory NVRAM The IP security software performs a hash of the NPK value which it places in a special MIB attribute The NPK value stored in NVRAM is unique to the router It is used to encrypt the cipher and integrity keys before they are stored in the router MIB In the context of Border Gateway Protocols BGP 4 if the Tcp Authentication parameter is MD5 and the Tcp Md5 Key Storage parameter is Encryp
175. h to route data Reset to Disable if you do not want this interface to send out redirects For example in a frame relay network two stations on the same network may not be directly connected if the network is not fully meshed Thus in this case you would set the Redirect parameter to Disable 1 3 6 1 4 1 18 3 5 3 2 1 24 1 25 A 36 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Ethernet Arp Encaps Configuration Manager gt Protocols gt IP gt Interfaces ARP Ethernet ARP Ethernet ARP SNAP ARP Both Probe LSAP ARP Ethernet Probe LSAP ARP SNAP Probe LSAP ARP Both Probe LSAP Defines the data link encapsulation to use for ARP and HP Probe packets generated at this interface if the underlying medium is Ethernet This parameter is ignored if the underlying medium is anything other than Ethernet Depending on the selection you have made for the ARP Resolution parameter ARP Probe or ARP Probe select the appropriate encapsulation option If your address resolution scheme is ARP only select Ethernet encapsulation SNAP encapsulation or Ethernet SNAP encapsulation If your resolution scheme is HP Probe only select LSAP encapsulation If your resolution scheme is ARP Probe select Ethernet LSAP encapsulation SNAP LSAP encapsulation or Ethernet S
176. hat matches the policy If you are constructing a BGP 3 or BGP 4 accept policy keep in mind that the Injection List parameter does not perform route aggregation as defined in RFC 1654 To aggregate routes in a transit AS you must construct an announce policy and use the announce Advertise parameter MIB Object ID 1 3 6 1 4 1 18 3 5 3 2 6 9 1 9 308628 14 00 Rev 00 B 13 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Peer AS Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of autonomous system numbers each ranging from 1 to 65 535 Specifies one or more ASs This policy applies to BGP advertisements from peers in the autonomous systems on this list Use the default empty list to indicate that this policy applies to BGP advertisements from peers in any AS 1 3 6 1 4 1 18 3 5 3 2 6 9 1 10 Peer Address Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of IP addresses Specifies one or more BGP peers This policy applies to BGP advertisements from the peers on this list To indicate that this policy applies to BGP advertisements from
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178. he default empty list means match any list BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 7 1 16 308628 14 00 Rev 00 Routing Policies BGP 4 Specific Accept Policy Parameters Parameter Injection List Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies Default An empty list Options A list of network identifiers Function Specifies network IDs to be included in the routing table in place of the network IDs listed in the received advertisement Instructions Specify a non null value only if the Action parameter is set to Accept The values you enter in the injection list determine the action taken If you supply a list of network IDs these IDs are injected into the routing table instead of the actual received IDs If you use the default an empty list the actual received network IDs are injected into the routing table If you supply a list that includes the encoding 255 255 255 255 255 255 255 255 the actual received network IDs are injected into the routing table along with the other IDs in the injection list This allows insertion of an aggregate or default along with the actual network The only valid network ID that you can include in an injection list is the default ID 0 0 0 0 0 0 0 0 This parameter replaces the received routes with the default route and places the default route in the routing table This parameter associates the default route with the attributes of the best route t
179. he same destination among multiple equal cost paths This chapter describes how to configure route and traffic load balancing In both techniques IBGP uses equal cost multipath ECMP routes submitted to the IP routing table by the IGP OSPF or RIP in the AS The ECMP routes could also be static routes For information about ECMP routing see Chapter 4 Configuring and Customizing IP for BGP Configuring IBGP for Route and Traffic Load Balancing To configure an IBGP speaker for route balancing and traffic load balancing the IGP used in the AS OSPF for example must be configured for ECMP on all routers Figure 9 1 for example shows an AS containing six IP routers The routers with interfaces to internal links are running OSPF The routers with interfaces to both internal and external links are running OSPF and BGP 308628 14 00 Rev 00 9 1 Configuring IP Exterior Gateway Protocols BGP and EGP AS i i 1 AE BE JLo i OSPF OSPF i BGP_ BGP i 1 3 2 3 1 I I i 1 D 1 CEI Eee Z J Aree E _ i i OSPF 2 osPF OSPF i 3 2 i i l 4 1 i 1 FEI l a 2 i OSPF i l BGP i 3 i l Key ECMP OSPF routes from router F to router A IP0089A Figure 9 1 BGP OSPF Aut
180. his parameter to 255 255 255 255 1 3 6 1 4 1 18 3 5 3 2 1 24 1 8 308628 14 00 Rev 00 A 29 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Unnumbered Associated Address Select IP from the Select Protocols window and click on OK None Any valid IP address Specifies an address that IP uses when sourcing a packet RIP uses this address to make decisions about advertising subnets over the unnumbered interface RIP advertises subnets over the unnumbered interface if the subnets have the same mask as the associated address Specify the address of any numbered interface on the router If you are running RIP over the unnumbered interface and if you are using a subnet address as the associated address the local and remote associated addresses should have the same network number If you configure local and remote associated addresses using different network numbers you must use RIP2 mode 1 3 6 1 4 1 18 3 5 3 2 1 24 1 110 IP Interface Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt Interfaces Enable Enable Disable Enables or disables IP routing on this interface Set to Disable to disable IP routing over this circuit 1 3 6 1 4 1 18 3 5 3 2 1 24 1
181. ibute To override the Local Preference attribute select True and supply a value for the Local Preference Value parameter 1 3 6 1 4 1 18 3 5 3 2 6 10 1 28 B 50 308628 14 00 Rev 00 Routing Policies Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Local Preference Value Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Null Null or a route weight value Specifies an override value for the Local Preference attribute Enter a value and set the Local Preference Override parameter to True 1 3 6 1 4 1 18 3 5 3 2 6 10 1 29 Next Hop Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Null An IP address Overrides the Next Hop path attribute with the IP address you specify To allow the existing Next Hop attribute use the default null value 1 3 6 1 4 1 18 3 5 3 2 6 10 1 30 Atomic Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Automatic Automatic Force Ignore Allows control over the atomic path attribute By default the router automatically sets this parameter if it knows that certain networks in aggregate range have not been included in an aggregate advertisement T
182. ies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of IP addresses Specifies the IP address of one or more BGP peers This policy applies to BGP advertisements authored by a router on this list and applies only to BGP sourced routes and if BGP is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to BGP advertisements from any router EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 19 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 19 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 19 308628 14 00 Rev 00 B 39 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID From BGP AS Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of autonomous system numbers Specifies one or more autonomous system numbers This policy applies to BGP advertisements received from BGP peers in an AS on this list and applies only to BGP sour
183. iguration Manager window Customizing EGP The instructions in this chapter show you how to start EGP using default values For information about modifying EGP default values see Chapter 10 Customizing EGP Services Using the Circuitless IP Interface A circuitless IP interface has an IP address that does not map to a specific circuit If one or more of the router s IP interfaces becomes disabled this circuitless feature ensures that the router is always reachable using the circuitless IP interface address as long as a viable path to the router exists The IP router can support one circuitless IP interface IP traffic travels to and from the circuitless interface as it does to any other IP interface In addition the circuitless IP interface can receive packets from any application When you configure a circuitless IP interface note the following e You can configure one circuitless IP interface per router Additional circuitless IP interfaces will not initialize 3 6 308628 14 00 Rev 00 Starting BGP and EGP Services with Site Manager e You can add BGP to a circuitless interface e You must assign a unique IP address and subnetwork number to the circuitless IP interface e You cannot configure a circuitless IP interface in nonforwarding mode For information about using a circuitless interface for a BGP peer to peer session see Defining a Peer to Peer Session on page 6 2 Configuring an U
184. ill be used this must be at least 3 seconds There are two exceptions If one peer sends a zero holdtime then the nonzero holdtime is used If both peers send zero holdtimes then no holdtime is used and no periodic keepalive message is sent The calculated holdtime is the amount of time either peer will wait for a keepalive or update message before declaring the connection down Either accept the current Holdtime Timer value or set the parameter to 0 or some value greater than 2 seconds 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 13 KeepAlive Timer Configuration Manager gt Protocols gt IP gt BGP gt Peers 30 seconds Any decimal number in the range 1 to 2147483647 Specifies how often keepalive messages will be sent across this peer connection If a holdtime of 0 is negotiated no periodic keepalive messages are sent Otherwise the Keepalive timer is set to the smaller of this configured value and one third of the holdtime Either accept the current keepalive value or set this parameter to some value greater than 0 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 15 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Min AS Origination Interval Configuration Manager gt Protocols gt IP gt BGP gt P
185. imit the volume of debug level messages that BGP generates and logs If you allow BGP to log all debug level events the messages that BGP generates will quickly overrun and overwrite the log file You can use Site Manager to control BGP event messages Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Debug The Edit BGP Debug Parameters window opens 5 Set the following parameters Peer Local Remote Message Level Message Trace Switch Click on Help or see the parameter descriptions beginning on page A 22 6 Click on OK Site Manager returns you to the Configuration Manager window 5 30 308628 14 00 Rev 00 Configuring and Customizing BGP Configuring EBGP Route Flap Dampening The frequent change of network reachability information that can be caused by an unstable route is commonly referred to as route flap Route flap dampening is a technique for suppressing information about unstable routes BayRS supports dampening of unstable EBGP routes The route flap dampening mechanism performs the following functions e Determines the stability of an EBGP route e Suppresses the use and advertisement of unstable EBGP routes e Unsuppresses a route that has regained stability To determine the stability of a route in the IP
186. in a remote AS the address must be on the same subnet as the local interface 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 6 A 10 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Peer AS Configuration Manager gt Protocols gt IP gt BGP gt Peers None 1 to 65535 Identifies the autonomous system to which the BGP router at the remote end of this BGP peer connection belongs Enter the appropriate AS number 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 10 Local Address Configuration Manager gt Protocols gt IP gt BGP gt Peers None Any IP address Specifies the IP address of the interface on the local side of this BGP peer connection Enter the appropriate address 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 4 Peer Mode Configuration Manager gt Protocols gt IP gt BGP gt Peers None None Internal External Indicates the route reflector mode of the remote BGP peer If the peer is a node use the default None If the peer is a route reflector in the same cluster specify Internal If the peer is a route reflector in a different cluster specify External 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 35 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path
187. indow choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Delete BGP 3 Site Manager opens a window prompting Do you really want to delete BGP3 Click on OK Site Manager removes BGP 3 from all circuits on the router and returns you to the Configuration Manager window 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP To delete BGP 4 complete the following steps Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Delete BGP 4 Site Manager opens a window prompting Do you really want to delete BGP4 5 Click on OK Site Manager removes BGP 4 from all circuits on the router and returns you to the Configuration Manager window Starting EGP Before you can select a protocol to run on the router you must configure a circuit that the protocol can use as an interface to an attached network For information and instructions see Configuring WAN Line Services and Configuring Ethernet FDDI and Token Ring Services 308628 14 00 Rev 00 Starting BGP and EGP Services with Site Manager When you have successfully configured the circuit the Select Protocols window opens Complete
188. ing template lt name gt name is the name of the template that you want to apply to the unstable route 308628 14 00 Rev 00 5 33 Configuring IP Exterior Gateway Protocols BGP and EGP 3 Match the accept policy to the unstable route For instructions see Specifying Matching Criteria fora BGP Accept Policy on page 7 8 For example the following sequence of commands creates a BGP accept policy named fred that causes BGP to apply the route flap dampening template steady to updates for network 3 4 5 6 bgp accept fred accept fred bgp action accept accept fred bgp route damping enabled accept fred bgp route damping template steady accept fred bgp match match bgp accept fred network 3 4 5 6 16 exact network 3 4 5 6 255 255 0 0 exact bgp accept fred 5 34 308628 14 00 Rev 00 Configuring and Customizing BGP Using Site Manager To create a route flap dampening template complete the following tasks Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Accept Policies The BGP4 Accept Policy Filters window opens 6 Click on Route Flap The Route Flap Dampening List window opens 7 Click on Add The Route Flap Dampening Configuration window opens
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190. initiate a connection on each interface configured for peer to peer communications If the attempt is unsuccessful BGP retries every 120 seconds You can use the BCC or Site Manager to specify a retry interval or disable the initiation function by setting the retry parameter to 0 6 4 308628 14 00 Rev 00 Using the BCC Navigate to a BGP peer prompt and enter retry lt interval gt Establishing a Peer to Peer Session interval is the number of seconds between attempts to initiate a peer to peer session For example the following command causes BGP to retry every 60 seconds to establish a peer to peer session between IP interfaces 2 2 2 2 and 2 2 2 3 peer 2 2 2 2 2 2 2 3 retry 60 peer 2 2 2 2 2 2 2 3 Using Site Manager Site Manager Procedure You do this 1 In the Configuration Manager window choose Protocols System responds The Protocols menu opens want to edit BGP peer parameters 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you 6 Click on BGP Peers 7 Click on the peer for which you want to edit parameters The BGP Peer List window opens The parameters for that peer appear in the window Set the Connect Retry Timer parameter Click on Help or see the parameter description on page A 13 Click on Apply and then click on
191. is System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters Set the Local AS to Advertise to Peer parameter Click on Help or see the parameter description on page A 15 The parameters for that peer appear in the window Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window By default a BGP speaker sends update messages with a maximum size of 800 bytes You can use the BCC or Site Manager to specify a maximum update message size overriding the default 308628 14 00 Rev 00 Establishing a Peer to Peer Session Note that if the update message that advertises a single route is larger than the configured message size the actual message size can exceed the configured value Using the BCC Navigate to a BGP peer specific prompt and enter max update size lt byies gt bytes is an integer indicating the maximum size of updates that BGP sends on this peer session For example the following command specifies a maximum size of 950 bytes for
192. is a group of destinations that share some common property BGP OSPF Interaction RFC 1403 defines the interaction between BGP and OSPF when OSPF is the IGP within an autonomous system For routers running both protocols the OSPF router ID and the BGP identifier must be an IP address and must be identical A route policy must be configured to allow BGP advertisement of OSPF routes Interaction between BGP 4 and OSPF includes the ability to advertise supernets to support classless interdomain routing CIDR BGP 4 allows interdomain supernet advertisements OSPF can carry supernet advertisements within a routing domain BGP 4 Confederations The BGP confederation feature can reduce the size and complexity of an IBGP mesh by breaking large autonomous systems into a confederation of smaller subautonomous systems This division reduces the size of IBGP meshes and the complexity of the associated configuration management Other autonomous systems view the confederation as a single autonomous system with the confederation ID as its AS number BGP confederations are available only with BGP 4 The BGP 4 confederation feature complies with RFC 1965 and provides the following functions 308628 14 00 Rev 00 Exterior Gateway Protocols BGP EGP e Lets you configure a confederation ID on the router e Implements new AS_PATH segment types e Lets you configure new AS_PATH variables AS_CONFED_SET and AS_CONFED_SEQUENCE for specifying co
193. is an active circuit on the router If the remote peer is located in a different AS from the local peer the remote address must be on the same subnet as the local address To override this restriction see Enabling Multihop Connections on page 5 11 If the local peer and the remote peer are located in the same AS BGP assumes that you are configuring an IBGP session and does not impose this restriction You can use the BCC or Site Manager to supply this information Using the BCC Navigate to the BGP prompt and enter peer local lt ocal_address gt remote lt remote_address gt as lt as_number gt local_address is the IP address of the local interface remote_address is the IP address of the remote interface as_number is the number of the AS in which the remote peer is located For example the following command defines a session with a remote peer in AS 5 The local IP interface is 2 2 2 2 The interface for the remote peer is 2 2 2 5 bgp peer local 2 2 2 2 remote 2 2 2 5 as 5 peer 2 2 2 2 2 2 2 5 5 6 2 308628 14 00 Rev 00 Using Site Manager Establishing a Peer to Peer Session Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the
194. it Discriminator metric is to be advertised for a network matching this policy and if advertised what value to use Select None to indicate that no value is to be advertised Select Specified to indicate that the value you specify for the Multi Exit Discriminator Value parameter is to be used Select Originating to indicate that the metric from the originating protocol is to be used This parameter is valid only if the Action parameter is set to Propagate 1 3 6 1 4 1 18 3 5 3 2 6 10 1 24 B 48 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Multi Exit Discriminator Value Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Null Null or a metric value Specifies a metric for the Multi Exit Discriminator attribute To advertise a multi exit discriminator value set the Action parameter to Propagate and set the Multi Exit Discriminator parameter to Specified 1 3 6 1 4 1 18 3 5 3 2 6 10 1 25 Origin Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies As Is As Is IGP EGP Incomplete Specifies an Origin attribute override The Origin attribute of a route matching this policy will be replaced with the indicated value To allow the existing Origin attribute use the defau
195. iterion as an object When you press Enter the BCC creates an object and displays an object specific prompt To specify multiple criteria create multiple objects 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Accept Policies The BGP4 Accept Policy Filters window opens 6 Set the following parameters Enable Name Networks Action Route Preference Rule Precedence Injection List Peer As Originating As Route Origin Aggregator As List Aggregator Router List Local Preference Bgp4 Preference As Weight Class As Pattern BGP Communities to match As Prepend BGP Community to accept BGP Community attribute action Route Flap Dampening Route Flap Dampening Template Click on Help or see the parameter descriptions beginning on page B 2 7 Click on OK Site Manager returns you to the BGP4 Accept Policy Filters window 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Defining a BGP Announce Policy BGP announce policies govern which routes BGP propagates to othe
196. ject ID Site Manager Parameters MAC Address Configuration Manager gt Protocols gt IP gt Adjacent Hosts None Depend on the data link you have selected Specifies the physical address of the adjacent host This value can be a 48 bit Ethernet address a 64 bit SMDS address an ATM PVC VPI VCI address or for an ATM SVC the address of the ATM interface Enter the MAC address as a 12 digit hexadecimal number Enter an ATM PVC address in the form virtual path identifier virtual channel identifier for example 0 32 1 3 6 1 4 1 18 3 5 3 2 1 6 1 6 Host Encapsulation Configuration Manager gt Protocols gt IP gt Adjacent Hosts Ethernet Ethernet SNAP PDN DDN SNAPIP NULL Specifies the adjacent host s encapsulation method Select Ethernet or SNAP Service Network Access Point if you are defining a point to point network interface or if the adjacent host resides on an Ethernet For an X 25 interface select PDN or DDN For an adjacent host on an ATM logical IP subnet select SNAP SNAPIP and NULL also specify host encapsulation methods for ATM networks 1 3 6 1 4 1 18 3 5 3 2 1 6 1 7 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID
197. k on Help or see the parameter description on page A 44 5 Click on OK Site Manager returns you to the Configuration Manager window Configuring the Router for Forwarding Mode By default IP forwards all packets that are not addressed to itself Use the forwarding mode to direct the IP router to route forward IP traffic Forwarding configures the IP router to process all broadcast packets and all IP packets explicitly addressed to it and to route all other IP packets Note BGP will not operate with an IP router in not forwarding host only mode Make sure that the routers you want BGP to operate with are in forwarding mode You can use the BCC or Site Manager to select the forwarding mode Using the BCC Navigate to the IP global prompt and enter forwarding lt mode gt mode is one of the following forwarding default notforwarding 4 4 308628 14 00 Rev 00 Configuring and Customizing IP for BGP For example the following command puts the router in forwarding mode ip forwarding forwarding ip Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose Global The Edit IP Global Parameters window opens 4 Set the Forwarding parameter Click on Help or see the parameter description on page A 44 5 Click on OK
198. k parameter 4 13 A 53 Node Protection Key BGP parameter A 18 Nonlocal ARP Destination parameter A 46 Nonlocal ARP Source parameter A 45 Nortel BGP Best Route Calculation Cisco equivalent C 11 Nortel Networks AS_Path pattern matching C 13 Nortel Networks AS_Path pattern matching symbols C 13 O OSPF BGP interaction 1 10 P Peer Address parameter BGP peer 3 2 A 10 in multiple RR cluster configuration 8 8 in peer to peer session definition 6 3 in route reflector cluster configuration 8 6 in RR client configuration 8 11 in single route reflector configuration 8 4 Peer AS parameter BGP peer 3 2 A 11 in multiple RR cluster configuration 8 8 in peer to peer session definition 6 3 308628 14 00 Rev 00 in route reflector cluster configuration 8 6 in RR client configuration 8 11 in single route reflector configuration 8 4 peer local command 6 2 Peer Local Remote parameter 5 30 A 22 Peer Max Update Size parameter 6 15 A 15 Peer Route Echo Switch parameter 6 17 A 16 peer to peer communications interval for establishing 6 4 policy parameters Action accept B 5 Action announce B 27 Advertise announce B 30 Aggregator AS List accept B 15 Aggregator Router List accept B 15 AS List Accept B 8 AS Path Override announce B 45 AS Pattern announce B 52 AS Prepend accept B 17 As Prepend announce B 54 AS Weight Class accept B 16 Atomic announce B 51 BGP Communities
199. l advertisement timer Using the BCC Navigate to a BGP peer specific prompt and enter advertise time lt seconds gt seconds is an integer specifying how often BGP issues an update message on this peer session For example the following command sets the external advertisement timer to 20 seconds for the peer session established between interfaces 2 2 2 2 and 2 2 2 5 peer 2 2 2 2 2 2 2 5 5 advertise time 20 peer 2 2 2 2 2 2 2 5 5 Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens continued 308628 14 00 Rev 00 6 9 Configuring IP Exterior Gateway Protocols BGP and EGP Site Manager Procedure continued You do this 4 Choose Peers System responds The IP Interface List for BGP window opens 5 Click on the IP interface for which you 6 Click on BGP Peers want to edit BGP peer parameters The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window 8 Set the External Advertisement Timer parameter Click on Help or see the parameter description on page A 13 9 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Specifying a H
200. licy type accept or announce per protocol To configure more than 32 accept or announce policy rules for a protocol you must set this parameter to a larger value IP will round the value up to the next multiple of 32 1 3 6 1 4 1 18 3 5 3 2 1 1 15 Route Filter Support Configuration Manager gt Protocols gt IP gt Global Enable Enable Disable Specifies whether or not IP supports route filters If you do not require support for route filters select Disable Otherwise use the default 1 3 6 1 4 1 18 3 5 3 2 1 1 16 Multiple Nexthop Calculation Method Configuration Manager gt Protocols gt IP gt Global Disable Enable Disable Enables and disables equal cost multipath support for RIP and OSPF and specifies the method that IP uses to choose the next hop when more than one is available Three methods are available round robin selection selection based on the source addresses IP forwards all packets with the same source address to the same next hop and selection based on the source and destination address IP forwards all packets with the same source and destination address to the same next hop Configure RIP and OSPF to support equal cost routes to the same destination 1 3 6 1 4 1 18 3 5 3 2 1 1 18 308628 14 00 Rev 00 A 49 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options
201. lize Setting the slot mask bit parameter to 1 on an empty slot a slot containing a system resource module or a slot with no IP support does not affect the circuitless IP interface 1 3 6 1 4 1 18 3 5 3 2 1 24 1 27 A 40 308628 14 00 Rev 00 Site Manager Parameters Parameter Forward Cache Size Path Configuration Manager gt Protocols gt IP gt Interfaces Default 128 entries Options 64 entry minimum no maximum Function Specifies the maximum number of entries allowed in the forwarding table at one time Instructions Specify a forwarding table size for each interface This parameter controls the number of destinations that are cached in the forwarding table on this receiving interface When this interface receives an IP packet the router looks up the destination in the forwarding table Therefore an interface that receives packets for a large number of destinations may benefit from a larger forwarding table The larger the number of entries the more likely it is that the destination will already be in the forwarding table and the faster the route lookups will be for those destinations Configuring a forwarding table size that is larger than necessary reduces the total amount of memory usable by other applications Configuring a routing table too small can affect overall router performance A check of the number of cache hits and misses will help determine the optimal size of the forwarding table For debugging purposes if
202. logy Within the AS clusters are connected in arbitrary topologies From the point of view of the topology a cluster is a mini AS Like an AS a cluster can be configured in an arbitrary way 8 6 308628 14 00 Rev 00 Configuring a Route Reflector You can use the BCC or Site Manager to perform the following operations e Associate a route reflector with a cluster e Establish a peer to peer session with a server in another cluster Using the BCC To associate a route reflector with a cluster navigate to the BGP global prompt and enter cluster id lt cluster_id gt cluster_id is the ID number of the cluster in which the route reflector is located For example the following command associates the route reflector with cluster 5 bgp cluster id 5 bgp To establish a peer to peer session with a route reflector in another cluster navigate to the BGP global prompt and enter peer local lt ocal_reflector_address gt remote lt remote_reflector_address gt as lt as_number gt local_reflector_address is the IP address of an interface on the local route reflector remote_reflector_address is the IP address of an interface on the remote reflector in another cluster as_number is an integer identifying the AS in which the remote server is located When the session specific prompt appears enter the following command to specify that the remote peer is a route reflector in another cluster peer mode reflector ext
203. ls menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP Enable parameter Click on Help or see the parameter description on page A 2 6 Click on OK Site Manager returns you to the Configuration Manager window 7 Inthe Configuration Manager window The Protocols menu opens choose Protocols 8 Choose IP The IP menu opens 9 Choose BGP The BGP menu opens 10 Choose BGP 3 Global The Edit BGP 3 Global Parameters menu opens 11 Set the Enable parameter Click on Help or see the parameter description on page A 10 12 Click on OK Site Manager returns you to the Configuration Manager window 13 In the Configuration Manager window The Protocols menu opens choose Protocols 14 Choose IP The IP menu opens 15 Choose BGP The BGP menu opens 16 Choose BGP 4 Global The Edit BGP 4 Global Parameters window opens 17 Set the Enable parameter Click on Help or see the parameter description on page A 10 18 Click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Supplying a BGP Identifier The BGP identifier is the IP address of an interface on this router There is no default for this parameter You must supply a BGP ID using the IP address of one
204. ls the way the router echoes a BGP route that is selected for forwarding Echoing in this case means advertising the route back to the peer from which it was received If this parameter is enabled the router advertises the route back as reachable and includes the local AS If this parameter is disabled the router echoes the route as unreachable withdrawn A BGP speaker that participates in inter AS multicast routing must advertise a route it receives from one of its external peers If the router stores the route in its routing table it must also advertise it back to the peer from which the route was received For a BGP speaker that does participate in inter AS multicast routing such echoing is optional If the peer router saves routes that contain its own AS number and is running short of memory send an unreachable echo 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 33 Loop Detection Configuration Manager gt Protocols gt IP gt BGP gt Peers Enabled Enabled Disabled Specifies whether BGP terminates a peer to peer session if it discovers a loop in the AS path Set this parameter as required 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 41 A 16 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters N
205. lt 1 3 6 1 4 1 18 3 5 3 2 6 10 1 26 308628 14 00 Rev 00 B 49 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Replace As Path Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Null An AS path Specifies an AS path that overrides the AS path attribute of a route matching this policy Constructs a BGP 4 AS path composed of AS path segments Each AS path segment includes a path segment type a path segment length specifying the number of ASs in the segment and a path segment value containing one or more AS numbers There are two AS path segment types type 1 an unordered set of ASs that a route in the UPDATE message has traversed and type 2 an ordered set of ASs that a route in the UPDATE message has traversed 1 3 6 1 4 1 18 3 5 3 2 6 10 1 27 Local Preference Override Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies False False True Indicates whether or not you are supplying an override value for the Local Preference path attribute in the routing Update message The Local Pref attribute is valid only in an Update advertised to an IBGP peer If you select False the router uses the IP route weight value to calculate the LOCAL_PREF path attr
206. n EGP or RIP defect rather it is caused by the way RIP aggregates subnets into natural networks EGP will operate over a subnetted interface between two Nortel Networks routers if a static route is implemented The router accepting the subnet from the remote network must augment the single subnet information with a static route for the entire remote network 308628 14 00 Rev 00 10 5 Configuring IP Exterior Gateway Protocols BGP and EGP Customizing EGP on the Router You customize EGP on the router by setting EGP global parameters as described under the following topics Topic Page Enabling and Disabling EGP 10 6 Supplying a Local AS Number 10 7 Enabling and Disabling EGP When you start EGP on the router EGP is automatically enabled for operation You can use Site Manager to disable and reenable EGP Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose EGP The EGP menu opens 4 Choose Global The Edit EGP Global Parameters window opens 5 Set the Enable parameter Click on Help The Values Selection window opens or see the parameter description on page A 24 6 Click on OK Site Manager returns you to the Configuration Manager window 10 6 308628 14 00 Rev 00 Supplying a Local AS Number Customizing EGP Services Ea
207. n originate time 30 peer 2 2 2 2 2 2 2 5 5 6 12 308628 14 00 Rev 00 Using Site Manager Establishing a Peer to Peer Session Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window 8 Set the Min AS Origination Interval parameter Click on Help or see the parameter description on page A 15 9 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 6 13 Configuring IP Exterior Gateway Protocols BGP and EGP Overriding the Local AS Number By default a BGP speaker that issues an open message to initiate a peer to peer session uses the AS number that you set with the Local AS parameter You can use Site Manager to include a different AS number overriding the default or use the AS number you specified in the Local AS parameter Using Site Manager Specifying a Maximum Update Size Site Manager Procedure You do th
208. ncrypted bgp 308628 14 00 Rev 00 5 25 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Peers The Edit BGP Global Parameters window opens 5 Set the following parameters Tcp Authentication Tcp Md5 Key Storage Tcp Md5 Key Click on Help or see the parameter descriptions beginning on page A 17 6 Click on OK Site Manager returns you to the Configuration Manager window Disabling BayRS Local Preference Calculation and Route Selection A BGP speaker calculates a local preference value for each route that it receives from an external peer and passes this value as the local_pref attribute in routing updates that it announces to its internal BGP IBGP peers A BGP speaker that receives a routing update from an IBGP peer uses the local_pref attribute in its best route selection process By default BGP calculates a local preference value by using the algorithm 6 described in Calculating BGP 4 Local Preference Values on page 5 27 The best route selection process is described in Best Route Selection on page 5 28 Different implementations of BGP have different ways of arriving at a local preference value However within an AS all
209. nd EGP Table C 1 Cisco to Nortel Networks BGP Translation Item Cisco Configuration Text BCC Command Site Manager Logical Steps 1 router bgp 333 ip bgp router id 1 1 1 1 Protocols gt IP gt BGP neighbor 1 1 1 2 remote as local as 333 IP Address 1 1 1 1 444 peer 1 1 1 1 1 1 1 2 Subnet Mask 255 0 0 0 as 444 Identifier 1 1 1 1 Local AS 333 Peer Address 1 1 1 2 Peer AS 444 Local Address 1 1 1 1 2 network 1 1 1 0 ip bgp Protocols gt IP gt Policy Filters gt mask 255 255 255 0 announce OutgoingRoutes BGP 4 gt Announce Policies gt Add action announce Name OutgoingRoutes modify advertise 1 1 1 0 24 Action ANNOUNCE Advertise gt List Network Number 1 1 1 0 Network Mask 255 255 255 0 3 neighbor 1 1 1 1 ip bgp Protocols gt IP gt Policy Filters gt distribute list 5 in accept IncomingRoutes BGP 4 gt Accept Policies gt Add access list 5 permit action accept match Name IncomingRoutes 128 1 0 0 0 0 255 255 network 128 1 0 0 Action ACCEPT 255 255 0 0 range back Network List gt List peer 1 1 1 1 Network Number 128 1 0 0 Network Mask 255 255 0 0 Match Criteria range Peer Address 1 1 1 1 4 neighbor 1 1 1 1 ip bgp Protocols gt IP gt Policy Filters gt distribute list 10 out announce OutgoingRoutes BGP 4 gt Announce Policies gt Add access list 10 permit action announce Name OutgoingRoutes 195 89 32 0 0 0 31 255 modify Action ANNOUNCE advertise 195 89 32 0 Advertise List gt List 255 255 224 0 Network Number 195 89 32 0 back
210. nd EGP Adjacent Host Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt Adjacent Hosts Enable Enable Disable Specifies the state active or inactive of the adjacent host in the IP routing tables Select Disable to make the adjacent host record inactive in the IP routing table the IP router will not consider this adjacent host Select Enable to make the adjacent host record active again in the IP routing table 1 3 6 1 4 1 18 3 5 3 2 1 6 1 2 Adjacent Host Address Configuration Manager gt Protocols gt IP gt Adjacent Hosts None Any valid IP address Specifies the IP address of the device for which you want to configure an adjacent host Enter the IP address 1 3 6 1 4 1 18 3 5 3 2 1 6 1 3 Next Hop Interface Addr Configuration Manager gt Protocols gt IP gt Adjacent Hosts 0 0 0 0 A valid IP address Specifies the IP address of the router s network interface to the adjacent host Enter the IP address in dotted decimal notation 1 3 6 1 4 1 18 3 5 3 2 1 6 1 4 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Ob
211. nd Terminology 10 2 EGP Implementation Notes 10 Customizing EGP on the Router 10 6 Configuring a Neighbor 10 8 10 1 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP EGP Concepts and Terminology EGP 2 is an exterior gateway protocol used to exchange network reachability information between routers in different autonomous systems In each AS routers share routing information using one or more interior gateway protocols for example RIP or OSPF The routers that serve as end points of a connection between two ASs run an exterior gateway protocol such as EGP 2 Figure 10 1 AS1 AS2 BGP connection Figure 10 1 IP00026A EGP Connection Between Two Autonomous Systems Running RIP The Nortel Networks implementation of EGP complies with RFCs 827 and 904 It runs over the same LAN and WAN media protocols that IP runs over including Ethernet token ring synchronous Wellfleet Proprietary Synchronous frame relay SMDS X 25 DDN PDN Pt to Pt ATM PVC FDDI T1 E1 HSSI and PPP Note EGP assumes that each advertised network is a natural class network A B or C based on its high order bits EGP cannot advertise or interpret subnets or supernets 10 2 308628 14 00 Rev 00 Customizing EGP Services An EGP router does the following e Acq
212. ndow The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 5 Click on the IP interface for which you want to edit BGP peer parameters 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to The parameters for that peer appear in edit parameters the window 8 Set the Keepalive Timer parameter Click on Help or see the parameter description on page A 14 9 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 6 8 308628 14 00 Rev 00 Establishing a Peer to Peer Session Setting the External Advertisement Timer After a connection is established the BGP speaker uses one or more update messages to send the entire IP routing table compliant with local BGP export policies BGP however does not require the entire routing table to be sent again Therefore the BGP speaker must keep a current version of the routing information received from all of its peers for as long as the connection to each peer is valid This information is updated via update messages whenever changes occur By default BGP examines the routing table for changes every 5 seconds If a change has occurred BGP issues an update message on the connection You can use the BCC or Site Manager to specify a value for the externa
213. nds 120 to 480 seconds Specifies the time period in seconds between the local EGP neighbor s EGP Poll message retransmissions This variable represents the RFC 904 T2 timer Either accept the default value of 180 seconds for this parameter or set it to some value from 120 to 480 seconds 1 3 6 1 4 1 18 3 5 3 2 4 3 1 10 308628 14 00 Rev 00 A 27 Configuring IP Exterior Gateway Protocols BGP and EGP IP Parameters Topic Page IP Configuration Parameters A 28 IP Interface Parameters A 30 IP Global Parameters A 44 Static Route Parameters A 51 Adjacent Host Parameters A 54 IP Configuration Parameters Parameter Path Default Options Function Instructions MIB Object ID IP Address Select IP from the Select Protocols window and click on OK None 0 0 0 0 or any valid IP address Assigns a 32 bit IP address to the interface Enter the IP address of the interface in dotted decimal notation Enter 0 0 0 0 to configure an unnumbered interface on the circuit 1 3 6 1 4 1 18 3 5 3 2 1 24 1 4 A 28 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Subnet Mask Select IP from the Select Protocols window and click on OK None The Configuration Manager automatically calculates an appropriate sub
214. net mask depending on the class of the network to which the interface connects However you can change the subnet mask with this parameter Specifies the network and subnetwork portion of the 32 bit IP address Either accept the assigned subnet mask or enter another subnet mask in dotted decimal notation Enter 0 0 0 0 if you are configuring an unnumbered interface on the circuit 1 3 6 1 4 1 18 3 5 3 2 1 24 1 6 Transmit Beast Addr Select IP from the Select Protocols window and click on OK 0 0 0 0 0 0 0 0 or any valid IP broadcast address Specifies the broadcast address that this IP subnet uses to broadcast packets Accepting 0 0 0 0 for this parameter specifies that the IP router will use a broadcast address with a host portion of all 1s Accepting 0 0 0 0 does not configure the router to use the address 0 0 0 0 to broadcast packets For example if you have IP address 123 1 1 1 and a subnet mask of 255 255 255 0 accepting the default value 0 0 0 0 configures the IP router to use the address 123 1 1 255 to broadcast packets To set the explicit broadcast address of all 1s enter 255 255 255 255 for this parameter Accept the default 0 0 0 0 unless the calculated broadcast address host portion of all 1s is not adequate If this is the case then enter the appropriate IP broadcast address in dotted decimal notation If you set the IP Address parameter to 0 0 0 0 to configure an unnumbered interface Site Manager automatically sets t
215. network interface serves the subnet 128 10 2 1 with a subnet mask of 255 255 255 0 the IP router considers any datagram with a destination address of 128 10 255 255 or 128 10 0 0 to be an ASB datagram Specify Enabled if you want the IP router to flood ASBs out this interface specify Disabled to restrict the router from flooding ASBs out this interface 1 3 6 1 4 1 18 3 5 3 2 1 24 1 14 Address Resolution Type Configuration Manager gt Protocols gt IP gt Interfaces ARP ARP X 25_DDN X 25_PDN INARP ARPINARP NONE X 25 BFEDDN PROBE ARPPROBE Indicates the address resolution scheme for this interface The default option ARP enables ARP on this interface The option INARP Inverse ARP enables the address resolution for frame relay interfaces It is used to discover the IP address of the station at the remote end of the virtual circuit The PROBE option enables HP Probe for Ethernet interfaces Depending on your network requirements select INARP only when all frame relay stations support Inverse ARP Select ARPINARP for your frame relay interfaces ARPINARP enables both ARP and Inverse ARP Select X 25_ DDN for your X 25 DDN interfaces Select X 25_PDN for your X 25 PDN interfaces Select PROBE to enable HP Probe on the interface Select ARPPROBE to enable both ARP and HP Probe 1 3 6 1 4 1 18 3 5 3 2 1 24 1 15 308628 14 00 Rev 00 A 33 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter
216. nfederation parameters e Implements correct AS_PATH setting and manipulation to neighboring autonomous systems that are within and outside the confederation See Configuring BGP 4 Confederations on page 5 17 for a detailed description of this feature and for configuration information BGP 4 TCP MD5 Message Authentication BGP 4 lets you configure the authentication of BGP messages by TCP MD5 signatures in compliance with RFC 2385 Protection of BGP Sessions via the TCP MDS Signature Option When BGP authentication is enabled a BGP speaker can verify that the BGP messages it receives from its peers are actually from a peer and not from a third party masquerading as a peer See Configuring and Enabling MDS Authentication on page 5 21 for a detailed description of this feature and for configuration information BGP Implementation Notes The guidelines in the following list are crucial to successful BGP configuration Caution If you do not follow these guidelines BGP either will not work efficiently or will become disabled on the interfaces involved e BGP will not operate with an IP router in nonforwarding host only mode Make sure that the routers you want BGP to operate with are in forwarding mode e If you are using BGP for a multihomed AS one that contains more than one exit point Nortel Networks strongly encourages you to use OSPF for your IGP and BGP for your sole exterior gateway protocol or us
217. nnumbered IP Interface IP lets you configure an interface on a point to point connection without using an IP address Such an interface is called an unnumbered interface Point to point connections using unnumbered interfaces can be configured to advertise IBGP and static routes You associate each unnumbered interface with the IP address of any numbered interface on the router including the circuitless interface The router can support multiple unnumbered interfaces and multiple unnumbered interfaces can be associated with the same IP address Because all traffic over an unnumbered interface uses broadcast addressing at the link layer neither an adjacent host specification nor address resolution is required Using BGP Peers with an Unnumbered Interface BGP peers cannot be configured directly on an unnumbered interface For information about using Site Manager to configure a BGP peer to peer session on routers connected through unnumbered interfaces see Configuring Peers over an Unnumbered Point to Point Link on page 6 19 As with routes learned over numbered interfaces IP stores each route learned over an unnumbered interface in the routing table 308628 14 00 Rev 00 3 7 Configuring IP Exterior Gateway Protocols BGP and EGP The routing table entry for a route learned over an unnumbered interface contains the following values Next hop address 0 Next hop mask 0 Next hop interface Circuit number of the un
218. not consider equal cost multipath routes submitted by RIP or OSPF For more information about using ECMP for load balancing see Chapter 9 Configuring Route and Traffic Load Balancing By default equal cost multipath support is disabled on the router You can use the BCC or Site Manager to enable the feature and choose a distribution method Note To configure equal cost multipath ECMP for BGP you may also have to configure ECMP for RIP OSPF or static routes Using the BCC Navigate to the IP global prompt and enter ecmp method lt method gt method is one of the following disabled default roundRobin srcDestHash destinationHash 4 6 308628 14 00 Rev 00 Configuring and Customizing IP for BGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Global The Edit IP Global Parameters window opens 4 Set the Multiple Nexthop Calculation Method parameter Click on Help or see the parameter description on page A 49 5 Click on OK Site Manager returns you to the Configuration Manager window Enabling ISP Mode on the Router IP provides an Internet service provider ISP mode of operation In ISP mode IP does the following e Enables BGP as a soloist By default BGP runs as a soloist on all slots configured with IP inter
219. ntra AS parameter Click on Help or see the parameter description on page A 3 6 Click on OK Site Manager returns you to the Configuration Manager window 5 6 308628 14 00 Rev 00 Configuring and Customizing BGP Specifying Route Types for IBGP Advertisements If IBGP is enabled you can specify the types of routes that BGP advertises in IBGP sessions By default IBGP propagates only routes learned from external BGP peers You can use Site Manager to configure IBGP to propagate routes learned from all route sources excluding IBGP and OSPF interarea and intra area routes which IBGP never advertises You can use the BCC or Site Manager to specify the route type for IBGP advertisements Using the BCC Navigate to the BGP global prompt and enter redistribute protocols lt protocols gt protocols is one of the values listed in Table 5 1 Table 5 1 Route Types for BGP Advertisements Route Type Meaning bgp default BGP propagates routes learned from external BGP peers all BGP propagates routes from all route sources For example the following command configures BGP to advertise routes from all route sources bgp redistribute protocols all bgp 308628 14 00 Rev 00 5 7 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The
220. numbered interface Note Unnumbered interfaces cannot be pinged directly For this reason such interfaces can make it difficult to diagnose router problems 3 8 308628 14 00 Rev 00 Chapter 4 Configuring and Customizing IP for BGP You customize IP services for BGP by setting the BGP related IP parameters Customizing IP Global Parameters When you configure an IP interface on a slot IP is automatically configured globally on the slot with default values for all global parameters You customize global IP by modifying global IP parameters as described under the following topics Topic Page Navigating the BCC to the IP Global Prompt 4 2 Opening the Site Manager Window for IP Global Parameters 4 3 Disabling and Reenabling Global IP 4 3 Configuring the Router for Forwarding Mode 4 4 Enabling Equal Cost Multipath Support 4 5 Enabling ISP Mode on the Router 4 7 308628 14 00 Rev 00 4 1 Configuring IP Exterior Gateway Protocols BGP and EGP Navigating the BCC to the IP Global Prompt Beginning at the top level box prompt enter ip The IP global prompt appears To display the current values for all IP global parameters enter info For example the following command sequence invokes the IP global prompt and displays current values for IP global parameters box ip ip info on box state enabled forwarding forwarding ttl 30 cache timeout default mib table route
221. o Disabled To drop a packet for an unknown destination set this parameter to Drop To configure BGP to return an ICMP destination unreachable message to the sender set this parameter to Reject 1 3 6 1 4 1 18 3 5 3 2 5 1 1 23 Route with MED Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Specifies whether BGP considers the Multi Exit Discriminator attribute in the route selection process Set this parameter as required 1 3 6 1 4 1 18 3 5 3 2 5 1 1 24 308628 14 00 Rev 00 A 7 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID IBGP ECMP Method Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Disabled Disabled Route Balance Traffic Balance Specifies whether IBGP uses ECMP paths provided by the IGP for route balancing or traffic load balancing To configure IBGP to use IGP ECMP routes for route balancing set this parameter to Route Balance To configure IBGP to use IGP ECMP routes for traffic load balancing set this parameter to Traffic Balance 1 3 6 1 4 1 18 3 5 3 2 5 1 1 26 Local Pref Calculation Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enabled Enabled Di
222. o include the atomic attribute even if the router does not assume one is required set the parameter to Force 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID As Pattern Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Empty string Any regular expression or empty string Allows AS_PATH pattern matching Enter a valid regular expression to indicate an AS and its position in a path The policy applies to all routes whose AS path includes the AS in that position For example the expression 200 means that the policy applies to all routes whose AS_PATH attribute contains AS 200 as the last AS in the path 1 3 6 1 4 1 18 3 5 3 2 6 10 1 32 BGP Community to announce Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies An empty list A list of BGP communities Specifies a list of one or more BGP communitiesto associate with this policy Set the BGP Community attribute action parameter to Append or Replace and supply a list of communities as an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means
223. ocols BGP and EGP IP Global Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt IP gt Global This parameter defaults to Enable when you add IP support to a circuit Enable Disable Specifies the state of the IP router software Select Enable if you have previously disabled the IP router software and now wish to reenable it Select Disable to disable the IP router software In dynamic mode when you set this parameter to Disable you immediately prohibit all Site Manager communication with the router 1 3 6 1 4 1 18 3 5 3 2 1 1 2 Forwarding Configuration Manager gt Protocols gt IP gt Global Forwarding Forwarding Not Forwarding Specifies whether the IP router forwards IP traffic that is not explicitly addressed to it Select Forwarding if you want the IP router to route forward IP traffic Forwarding configures the IP router to process all broadcast packets and all IP packets explicitly addressed to it and to route all other IP packets Select Not Forwarding if you want to provide IP management access by means of TFTP and SNMP to all active IP interfaces but also want to prohibit the IP router from forwarding IP traffic You must specify an identical IP address and mask combination for each active IP interface that will provide management
224. of its local AS If you choose noncore mode the AS to which this EGP neighbor belongs will act as a stub AS That is it will advertise only networks that reside within the AS The default gateway mode is core mode If the EGP router is reconfigured to run in noncore mode the Site Manager automatically configures EGP export route filters on that IP interface This action suppresses OSPF external routes to EGP and the advertisement of any networks learned by EGP You can use Site Manager to specify the gateway mode of this EGP neighbor Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose EGP The EGP menu opens 4 Choose Neighbors The IP Interface List for EGP window opens 5 Click on the IP interface you want The parameter values for that interface appear in the window 6 Set the Gateway Mode parameter Click on Help or see the parameter description on page A 25 7 Click on Apply and then click on Done Site Manager returns you to the Configuration Manager window 10 10 308628 14 00 Rev 00 Customizing EGP Services Enabling and Disabling the Neighbor Relationship When you establish a neighbor to neighbor relationship on an interface the relationship is automatically enabled You can use Site Manager to temporarily disable this neighbor
225. of the router s IP interfaces You can use the BCC or Site Manager to supply a BGP identifier for the router Using the BCC Navigate to the BGP prompt and enter router id lt i p_address gt jp_address is the address of one of the IP interfaces on the router For example the following command supplies IP address 2 2 2 2 for the BGP identifier bgp router id 2 2 2 2 bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP Identifier parameter Click on Help or see the parameter description on page A 3 6 Click on OK Site Manager returns you to the Configuration Manager window 5 4 308628 14 00 Rev 00 Identifying the Local AS Configuring and Customizing BGP Each autonomous system in the internet has a unique AS ID You can use the BCC or Site Manager to supply the ID of the AS in which the BGP router is located Using the BCC Navigate to the BGP prompt and enter local as lt ocal_as gt local_as is the number of the AS in which the router is located For example the following command specifies AS 5 as the local AS bgp local as 5 bgp Using Site Manager Site Manager Procedure You do this System res
226. olddown Time The holddown time is the amount of time either peer will wait for a keepalive or update message before declaring the connection down A BGP speaker that initiates a connection inserts a holddown time value into the open message The peer responds with an open message that also contains a holddown time value If the BGP speakers establish a session they use the lesser value which must be greater than 2 There are two exceptions to this rule e If one peer sends a zero holddown time the peers use the nonzero holddown time on the session e If both peers send zero holddown times the peers observe no holddown time on the session By default BGP inserts a value of 90 seconds into the open message You can use the BCC or Site Manager to specify a holddown time value or to disable the holddown function by setting this value to 0 6 10 308628 14 00 Rev 00 Using the BCC Establishing a Peer to Peer Session Navigate to a BGP peer specific prompt and enter holddown lt seconds gt seconds is an integer indicating the number of seconds that BGP waits for a keepalive message before declaring the connection down For example the following command sets the holddown timer to 60 seconds for the peer session established between interfaces 2 2 2 2 and 2 2 2 5 peer 2 2 2 2 2 2 2 5 5 holddown 60 peer 2 2 2 2 2 2 2 5 5 Using Site Manager Site Manager Procedure You do this 1 In the Configur
227. olicy applies to RIP advertisements from routers on this list and applies only to RIP sourced routes and if RIP is included as a route source The BCC implements this matching criterion as an object To specify multiple items create multiple objects 308628 14 00 Rev 00 7 21 Configuring IP Exterior Gateway Protocols BGP and EGP Using Site Manager You can use Site Manager to configure a BGP 4 announce policy Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Announce Policies The BGP4 Announce Policy Filters window opens 6 Click on the policy that you want to edit continued 7 22 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Site Manager Procedure continued You do this System responds 7 Set the following parameters Enable Name Networks Action Rule Precedence Route Source Advertise From RIP Gateway Received on RIP Interface From OSPF Router ID Received OSPF Type Received OSPF Tag From EGP Peer From EGP AS From EGP Gateway From BGP Peer From BGP AS Received BGP Next Hop External Route Source Outbound Peer AS Outbound Peers
228. onfigure a BGP peer to peer session directly on an unnumbered interface To establish a connection each side of the connection must be associated with a numbered interface For example consider the two routers in Figure 6 2 Routers A and B are connected by a point to point network using unnumbered interfaces Both routers are configured with BGP Peer to Peer connection Network 1 Network 3 Point to Point network Router A Router B Numbered IP interface configured for a BGP peer to peer connection Unnumbered IP interface IPO049A Figure 6 2 BGP over an Unnumbered Point to Point Link 308628 14 00 Rev 00 6 19 Configuring IP Exterior Gateway Protocols BGP and EGP To establish a peer to peer session between router A and router B 1 4 Choose a numbered interface on each router for the peer to peer session Note the network subnet that each interface is on In Figure 6 2 router A has a numbered interface to network 1 Router B has a numbered interface to network 3 The network administrator has chosen these two interfaces to support the peer to peer session If the two routers are in different ASs enable multihop EBGP connections See Enabling Multihop Connections on page 5 11 If no interior gateway protocol RIP or OSPF is running over the unnumbered link configure a static route on each router to the other router s network and subnet Because the routers do no
229. onfiguring and Customizing BGP Table 5 6 Route Flap Dampening Template Parameters Parameter Value Default Meaning cutoff threshold Integer 2000 Specifies a maximum threshold 1 through 20 000 for the route penalty value reuse threshold Integer 750 Specifies a minimum threshold 1 through 20 000 for the route penalty value reachable decay Number of minutes 5 Specifies the number of minutes 1 through 45 that the route must remain reachable before BGP decrements the penalty value by half unreachable decay Number of minutes 15 Specifies the number of minutes 1 through 45 that the route must remain unreachable before BGP decrements the penalty value by half max hold down Number of minutes 45 Specifies the maximum number of minutes 1 through 60 that a route can remain suppressed memory limit Number of minutes 45 Specifies the maximum number of minutes 1 through 60 that the status of a route can remain unchanged reachable or unreachable before BGP resets the penalty value and flap count to 0 and unsuppresses the route To apply the template to an inbound BGP routing update 1 Create and name a BGP accept policy For instructions on creating a BGP accept policy see Defining a BGP Accept Policy on page 7 2 An accept policy specific prompt appears 2 Modify the accept policy by entering the following commands action accept route damping enabled route damp
230. only to OSPF sourced routes and if OSPF is included as a route source Specify one or more IP addresses Use the default empty list to indicate that this policy applies to OSPF updates from any router EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 13 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 13 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 13 308628 14 00 Rev 00 B 33 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Path Path Default Options Function Instructions MIB Object ID MIB Object ID MIB Object ID Received OSPF Type Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Announce Policies Any Type 1 Type 2 External Internal Any Specifies which types of OSPF routes match this policy and applies only to OSPF sourced routes and if OSPF is included as a route source To match any route type enter Any To match any non ASE route enter Internal To match any ASE route enter External To match any external type 1 route enter Type 1 To match any external type 2 route enter Type 2 EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 14 BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 14 BGP 4 1 3 6 1 4 1 18 3 5 3 2 6 10 1 14 B 34 308628 14 00 Rev 00 Routing Policies Parameter Path
231. onomous System Assume for this example that OSPF is configured throughout the AS to support ECMP routes and that all links in the AS have the same cost This means that the IP routing table in router F includes two ECMP routes to router A One route uses interface 1 the other route uses interface 4 Assume as well that the BGP speakers on routers A B and F have established a full mesh of IBGP peer to peer sessions with each other using routers C D and E 9 2 308628 14 00 Rev 00 Configuring Route and Traffic Load Balancing Now consider that BGP on router F receives advertisements to three destinations destination_1 destination_2 and destination_3 from its peer on router A For each of these destinations BGP must consult the IP routing table to determine the next OSPF hop If you configure BGP on router F for IBGP ECMP route balancing BGP submits one BGP route to the routing table for each BGP destination using in round robin fashion the available OSPF ECMP routes as follows 1 BGP submits a route to destination_1 and specifies interface 1 the interface to router D as the next hop 2 BGP submits a route to destination_2 and specifies interface 4 the interface to router C as the next hop 3 BGP submits a BGP route to destination_3 and specifies interface 1 as the next hop Figure 9 2 shows the three route balancing BGP ECMP entries to the routing table on router 4 Destination Mask Proto Age Cost Next
232. onomous systems that the routing information has passed through the AS path In addition an update includes the following e List of path attributes e Local preference value BGP 4 only described in Chapter 5 Configuring and Customizing BGP 1 8 308628 14 00 Rev 00 Path Attributes Exterior Gateway Protocols BGP EGP A BGP 3 update message contains a variable length sequence of path attributes each attribute consisting of an attribute value and an attribute description Table 1 1 describes the mandatory and optional BGP 3 path attributes Table 1 1 BGP 3 Path Attributes Attribute Description AS path Mandatory attribute containing a list of the ASs that must be traversed to reach the given destinations Origin Next hop Mandatory attribute containing one of the following values IGP the path is valid all the way to the IGP of the originating AS EGP the path was advertised using EGP by the last AS in the AS path Incomplete the path is valid only to the last AS in the AS path Mandatory attribute that defines the IP address of the router to use as a next hop for the advertised destinations Inter AS Unreachable Optional attribute used to choose between paths to the destinations listed Discretionary attribute used to indicate destinations that have become unreachable The BGP 4 update message has the same format and mandatory attributes as the BGP 3
233. ons BGP parameter 5 11 disabling BGP 5 2 dynamic policy configuration for BGP 5 13 EGP 10 6 equal cost multipath support 4 5 global IP 4 3 ISP mode 4 8 multihop connections for BGP 5 12 redundant connections for BGP 5 10 dynamic policy configuration for BGP enabling and disabling 5 13 E EBGP ECMP parameter 9 9 ebgp ecmp method command 9 7 ecmp method command 4 6 EGP deleting from the router 3 6 enabling and disabling 10 6 implementation notes 10 5 local AS number for 10 7 neighbor acquisition mode for 10 12 enabling and disabling 10 11 gateway mode for 10 10 poll mode for 10 13 specifying address of 10 9 timers for 10 14 neighbor reachability phase 10 4 network reachability phase 10 4 overview of 10 2 starting 3 4 EGP parameters Hello Timer 10 14 EGP parameters Hello Timer A 27 308628 14 00 Rev 00 Enable weights parameter A 22 Enable Default Route for Subnets parameter A 48 Enable ISP Mode Support parameter 4 8 A 50 Enable parameter adjacent host A 54 BGP peer A 12 BGP 3 5 3 A 10 BGP 4 5 3 A 10 EGP 10 6 A 24 EGP neighbor 10 11 A 26 global IP 4 4 A 44 IP static route A 51 Enable Security parameter A 41 enabling BGP 5 2 dynamic policy configuration for BGP 5 13 EGP 10 6 equal cost multipath support 4 5 global IP 4 3 ISP mode 4 8 multihop connections for BGP 5 12 redundant connections for BGP 5 10 equal cost multipath ECMP 1 8 IP 4 5
234. ow 308628 14 00 Rev 00 10 13 Configuring IP Exterior Gateway Protocols BGP and EGP Setting Neighbor Timers EGP uses two configurable timers the hello timer and the poll timer The hello timer determines the number of seconds between the local EGP neighbor s EGP hello message retransmissions This variable represents the RFC 904 T1 timer By default EGP sends a hello message every 60 seconds You can use Site Manger to supply a value between 30 and 120 seconds The poll timer determines the interval between the local EGP neighbor s EGP poll message retransmissions This variable represents the RFC 904 T2 timer By default EGP retransmits a poll message every 180 seconds You can use Site Manager to specify a value between 120 and 480 seconds Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose EGP 4 Choose Neighbors The EGP menu opens The IP Interface List for EGP window opens 5 Click on the IP interface for which you want to specify the neighbor s address The parameter values for that interface appear in the window 6 Set the following parameters Hello Timer Poll Timer Click on Help or see the parameter descriptions beginning on page A 27 7 Click on Apply and then click on Done Site Manager returns you to the Con
235. parameter value is one of the parameter value pairs described in Table 7 1 308628 14 00 Rev 00 7 3 Configuring IP Exterior Gateway Protocols BGP and EGP Table 7 1 BCC Definition Parameters for BGP Accept Policies Parameter Values Function state enabled default disabled Enables and disables the policy you have created action preference ignore default accept 1 default to 16 Specifies whether the protocol ignores a route that matches the policy or forwards the route to the routing table manager Assigns a metric value the higher the number the greater the preference to a route that the protocol forwards to the routing table manager If confronted with multiple routes to the same destination the routing table manager may need to use this value to decide which route to insert Routes for all networks 0 0 0 0 0 0 0 0 should have the lowest preference and routes for the most specific networks longest address and mask should have the highest preference precedence 0 default to any integer Assigns a metric value to this policy a policy with a higher value takes precedence over a policy with a lower value This value determines the order of precedence for policies that match the same route bgp4 preference 1 default to 16 Specifies a value that can be used to compare a route that matches this policy with other BGP 4 routes The larger the value the grea
236. pares the path attributes to choose the preferred path In addition to exchanging BGP information between autonomous systems you can use BGP to exchange BGP information between routers in the same AS To differentiate between these uses the latter is called interior BGP IBGP Exterior Gateway Protocol EGP You use the Exterior Gateway Protocol to exchange network reachability information between routers in different autonomous systems An interior gateway protocol IGP such as RIP or OSPF is used within an AS to facilitate the communication of routing information within an autonomous system The routers that serve as the end points of a connection between two autonomous systems also run an exterior gateway protocol such as EGP 2 Routers establish EGP neighbor relationships to periodically exchange reliable network reachability information EGP neighbors exchange complete reachability information not just updates The router uses this information to maintain a list of gateways the networks the gateways can reach and the corresponding distances Chapter 10 Customizing EGP Services describes the use of EGP 308628 14 00 Rev 00 1 3 Configuring IP Exterior Gateway Protocols BGP and EGP Classless Interdomain Routing Classless interdomain routing CIDR is an addressing scheme that uses supernet addresses to represent multiple IP destinations Rather than advertise a separate route for each destination in a supernet
237. pes for IBGP Advertisements 5 7 Setting the Update Interval Timer 59 Allowing Redundant Connections 5 10 Enabling Multihop Connections 5 11 Disabling and Reenabling Dynamic Policy Configuration 5 13 Configuring BGP as a Soloist 5 14 Associating a Route Reflector with a Cluster ID 5 15 Disabling and Reenabling Route Aggregation a5 Configuring BGP 4 Confederations Belz Enabling and Disabling Black Hole Punching 5 18 Disabling and Reenabling the BGP 4 MED Attribute 5 20 Configuring and Enabling MD5 Authentication 5 21 Disabling BayRS Local Preference Calculation and Route Selection 5 26 continued 308628 14 00 Rev 00 5 1 Configuring IP Exterior Gateway Protocols BGP and EGP Topic Page Configuring BGP Message Logging 5 30 Configuring EBGP Route Flap Dampening 5 31 Enabling and Disabling BGP When you start BGP on the router BGP is automatically enabled for both BGP 3 and BGP 4 peer to peer connections You can use the BCC and Site Manager to disable and reenable BGP on the router You can also use Site Manager to disable and reenable BGP 3 and BGP 4 Using the BCC Navigate to the BGP prompt and enter state lt state gt state is one of the following enabled default disabled 5 2 308628 14 00 Rev 00 Using Site Manager Configuring and Customizing BGP Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protoco
238. ponds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens Set the BGP Local AS parameter Click on Help or see the parameter description on page A 3 Click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 5 5 Configuring IP Exterior Gateway Protocols BGP and EGP Disabling and Reenabling IBGP Support By default BGP supports IBGP intra AS sessions For information see Chapter 1 Exterior Gateway Protocols BGP EGP A BGP transit AS should use IBGP intra AS routing A stub or multihomed AS usually does not use IBGP routing You can use the BCC or Site Manager to disable and reenable the feature Using the BCC Navigate to the BGP prompt and enter intra as routing lt state gt state is one of the following enabled default disabled For example the following command disables IGBP bgp intra as routing disabled bgp Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose BGP Global The Edit BGP Global Parameters window opens 5 Set the BGP I
239. pplication of the debug attributes to the BGP 4 gateway connections enter 255 255 255 255 for the remote IP address 1 3 6 1 4 1 18 3 5 3 2 5 1 5 1 2 A 22 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Message Level Configuration Manager gt Protocols gt IP gt BGP gt BGP Debug All All Debug Info Warning Fault Trace Specifies the severity level of event messages received Select the default to obtain event messages of all levels 1 3 6 1 4 1 18 3 5 3 2 5 1 5 1 4 Message Trace Switch Configuration Manager gt Protocols gt IP gt BGP gt BGP Debug Disable Disable Open Update Notification Keepalive Specifies whether or not BGP messages on the specified connection are logged and if so which messages are logged Use the default or select a BGP message type 1 3 6 1 4 1 18 3 5 3 2 5 1 5 1 5 308628 14 00 Rev 00 A 23 Configuring IP Exterior Gateway Protocols BGP and EGP EGP Parameters Topic Page EGP Global Parameters A 24 EGP Neighbor Parameters A 25 EGP Global Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Enable Configuration Manager gt Protocols gt I
240. r RIP For information about ECMP routing see Chapter 4 Configuring and Customizing IP for BGP You can configure an EBGP speaker to use ECMP static routes in the IP routing table for route balancing and traffic load balancing The following conditions must apply e The local BGP router and the remote BGP router must be connected by multiple links e IP must be configured on a circuitless interface on both the local and remote routers 308628 14 00 Rev 00 9 5 Configuring IP Exterior Gateway Protocols BGP and EGP e The EBGP speaker on the local router and the EBGP speaker on the remote router must establish a peer to peer session using their circuitless IP interfaces For information see Chapter 6 Establishing a Peer to Peer Session e The local IP routing table must contain multiple equal cost routes to the circuitless interface of the router in the remote AS These ECMP routes are typically submitted statically but they could also be submitted by OSPF or RIP In Figure 9 4 for example two BGP routers located in different ASs are connected by two physical links Peer to Peer Session IP circuitless interface ee ee eee ea eee Remote AS se ee a ee Local AS ee a a EEA N mmm A as a O EE Key ECMP static routes IPOO90A Figure 9 4 ECMP Static Routes Assume that the IP routing table in the BGP router in AS 1 contains two ECMP
241. r routers When BGP encounters an update that matches the policy it performs the action you specify To define a BGP announce policy you must do the following e Supply a name for the new announce policy e Specify whether BGP ignores or advertises an update that matches the policy e Rank policies according to precedence You can use the BCC or Site Manager to configure a BGP announce policy Using the BCC Navigate to the BGP global prompt and enter announce lt policy_name gt policy_name is a unique name for the BGP announce policy A policy specific prompt appears indicating that the BCC has created the policy using default values for all parameters For example the following command creates an announce policy named pol_1 bgp announce pol_1 announce pol_1 bgp In response to the prompt enter lt parameter gt lt value gt parameter value is one of the parameter value pairs shown in Table 7 4 308628 14 00 Rev 00 7 41 Configuring IP Exterior Gateway Protocols BGP and EGP Table 7 4 BCC Definition Parameters for BGP Announce Policies Parameter Values Function state enabled default Enables or disables this policy disabled action ignore default Specifies whether or not to advertise a route that propagate matches this policy precedence 0 default to any Specifies a metric value to be used to compare metric value this policy with other policies that a route may match A policy
242. rameters Note By default an external BGP 3 or BGP 4 speaker will neither advertise any routes to a peer nor inject any routes into its IGP Route policies must be configured to enable any route advertisement So that every BGP border router within an AS comes to the same decision in constructing path attributes for an external path routing policies must be coordinated among all BGP speakers within an AS Nortel Networks recommends that the accept and announce policies on all IBGP connections accept and propagate all routes On external BGP connections you must make consistent routing policy decisions Note In addition to announce and accept policies Nortel Networks supports import and export filters for BGP 3 Import and export filters provide a subset of the parameters provided by the policies For information about configuring import and export filters see Configuring IP ARP RARP RIP and OSPF Services When a BGP speaker receives a route in an update message it applies any local routing policies to determine whether the router will use the route and whether it will propagate the route to other routers Then if the route can be used it is compared against routes from other protocols and possibly included in the forwarding table 308628 14 00 Rev 00 7 1 Configuring IP Exterior Gateway Protocols BGP and EGP This chapter covers the following topics Topic Page Defining a BGP Accept Polic
243. ransit networks to the remaining ASs The IBGP connections between BGP routers A B and C are necessary to provide consistent information to the ASs IBGP Route Reflector A BGP router configured for IBGP must establish a peer to peer session with every other IBGP speaker in the AS In an AS with a large number of IBGP speakers this full mesh topology can result in high bandwidth and maintenance costs For example a full mesh topology for an AS with 50 IBGP speakers requires 1225 internal peer to peer connections 308628 14 00 Rev 00 1 7 Configuring IP Exterior Gateway Protocols BGP and EGP To avoid the high costs of a full mesh topology to support IBGP speakers within a large AS you can configure a router to function as an IBGP route reflector RR An IBGP speaker that needs to communicate with other BGP speakers in the AS establishes a single peer to peer RR client session with the IBGP route reflector For information about the IBGP route reflector see Chapter 8 Configuring a Route Reflector Equal Cost Multipath BGP equal cost multipath ECMP support allows a BGP speaker to perform route balancing within an AS by using multiple equal cost routes submitted to the routing table by OSPF or RIP For more information about BGP equal cost multipath see Configuring IP Multicasting and Multimedia Services BGP Updates BGP 3 and BGP 4 speakers exchange routing updates that include a network number and a list of aut
244. rks The only valid network ID that you can include in an injection list is the default ID 0 0 0 0 0 0 0 0 This parameter replaces the received routes with the default route and places the default route in the routing table This parameter associates the default route with the attributes of the best route that matches the policy If you are constructing a BGP 3 or BGP 4 accept policy keep in mind that this parameter does not perform route aggregation as defined in RFC 1654 To aggregate routes in a transit AS you must construct an announce policy and use the announce Advertise parameter MIB Object ID 1 3 6 1 4 1 18 3 5 3 2 6 7 1 9 308628 14 00 Rev 00 B 9 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Peer AS Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies An empty list A list of autonomous system numbers each ranging from 1 to 65 536 Specifies one or more autonomous systems This policy applies to BGP advertisements from peers in those ASs Use the default empty list to indicate that this policy applies to BGP advertisements from peers in any AS 1 3 6 1 4 1 18 3 5 3 2 6 7 1 10 Peer Address Configuration Manager g
245. route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 Weight Value 6 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 6 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 Weight Value 7 Configuration Manager gt Protocols gt IP gt BGP gt Weights 8 1 to 15 plus the infinity value of 16 Specifies the class 7 weight value to add to this AS This weight value is added to the other AS weight values in a route to determine the preference of the route and aid in route selection Either accept the current AS weight value or enter a new value Any route that traverses an AS with an AS weight of 16 infinity will not be used 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 5 308628 14 00 Rev 00 A 21 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID
246. routing table BGP maintains a penalty value for the route based on its recent history Each time the route flaps that is each time it is withdrawn from the routing table BGP increments this penalty value During the period of time that the route does not flap BGP decrements the penalty value In this way as the instability of the route increases the penalty value rises As the route becomes more stable the penalty value falls To monitor BGP for route flaps you set the route dampening parameter on a BGP accept policy that matches the route BGP creates a penalty value for the route and sets the value to 0 BGP increments the penalty each time the route flaps BGP provides a route flap dampening template that allows you to control the way BGP evaluates a route s penalty and how based on the penalty it decides to suppress or unsuppress the route The template consists of the following parameters e Cutoff threshold If the penalty value rises above the value that you specify as the cutoff threshold BGP suppresses the route e Reuse threshold If the penalty value falls below the value that you specify as the reuse threshold BGP unsuppresses the route e Reachable decay If the route is still reachable after the period of time that you specify BGP reduces the penalty value by half BGP uses a half life decay algorithm to decrement the penalty value e Unreachable decay If the route is still unreachable after the period of time
247. rs There are two AS path segment types type 1 an unordered set of ASs that a route in the update message has traversed and type 2 an ordered set of ASs that a route in the update message has traversed as prepend List of AS numbers Specifies AS numbers that BGP adds to an AS path before it adds the current AS to the path continued 308628 14 00 Rev 00 Table 7 5 Configuring BGP Accept and Announce Policies BCC BGP Announce Policy Parameter Overrides continued Parameter Values Function atomic aggregate automatic default force ignore Allows control over the atomic path attribute By default the router automatically sets this attribute if it knows that certain networks in aggregate range have not been included in an aggregate advertisement local preference false default true Indicates whether or not you are supplying an override value for the Local Preference path attribute in the routing update message The local pref attribute is valid only in an update advertised to an IBGP peer If you select False the router uses the IP route weight value to calculate the local_pref path attribute local pref override null default or a route weight value Specifies an override value for the local preference attribute igp egp incomplete med method none default Indicates whether or not a multiexit specified discriminator metric is to be adv
248. s Topic Page Starting IP and BGP 3 1 Starting EGP 3 4 Using the Circuitless IP Interface 3 6 Configuring an Unnumbered IP Interface 3 7 Starting IP and BGP You must start BGP as part of starting IP Before you can select a protocol to run on the router you must configure a circuit that the protocol can use as an interface to an attached network For information and instructions see Configuring WAN Line Services and Configuring Ethernet FDDI and Token Ring Services The instructions in this chapter show you how to start IP and BGP using default values 308628 14 00 Rev 00 3 1 Configuring IP Exterior Gateway Protocols BGP and EGP When you have successfully configured the circuit the Select Protocols window opens Complete the steps in the following table Site Manager Procedure You do this System responds 1 Inthe Select Protocols window select the The IP Configuration window opens following protocols IP BGP Then click on OK 2 Set the following parameters IP Address Subnet Mask Transmit Beast Addr UnNumbered Assoc Address Click on Help or see the parameter descriptions beginning on page A 28 3 Click on OK The BGP Configuration window opens 4 Set the following parameters Identifier Local AS Click on Help or ee the parameter descriptions on page A 2 5 Click on OK The BGP Peer window opens 6 Set the following param
249. s System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens 2 Choose IP The IP menu opens 3 Choose Global The Edit IP Global Parameters window opens Set the Enable ISP Mode Support parameter to Enable Click on Help or see the parameter description on page A 50 5 Click on OK The Edit Soloist Slot window opens 6 Choose a slot and click on OK Site Manager returns you to the Configuration Manager window 308628 14 00 Rev 00 Configuring and Customizing IP for BGP Defining a Static Route A static route is a manually configured route that specifies the transmission path a datagram must follow based on the datagram s destination address A static route specifies a transmission path to another network You configure a static route if you want to restrict datagrams to paths you specifically configure Static routes remain in IP routing tables until you remove them Note however that if the interface that was used to reach the next hop in the static route becomes disabled the static route disappears from the IP routing table You can use the BCC or Site Manager to specify the following e The state active or inactive of the static route record in the IP routing tables e The IP address of the network to which you want to configure the static route e The subnet mask of the destination network e The number of router hops
250. s gt IP gt Global 30 1 to 255 hops Specifies the starting value of the time to live TTL counter for each packet the router originates and transmits called a source packet When the router transmits a source packet the TTL counter starts to decrement Each router or hop that the packet traverses decrements the TTL counter by one When the counter reaches zero the router discards the packet unless it is destined for a locally attached network The TTL counter prevents packets from looping endlessly through the network Enter the maximum number of hops a source packet can traverse 1 3 6 1 4 1 18 3 5 3 2 1 1 5 A 46 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Zero Subnet Enable Configuration Manager gt Protocols gt IP gt Global Disable Enable Disable Specifies whether an interface address whose subnet portion is all zeros or all ones should be declared legal or not If you set this parameter to Enable then you can configure IP interfaces with a subnet ID of zero Setting this parameter to Disable prevents you from doing so Accept the default Disable if you do not have any interfaces that have a zero subnet ID Otherwise reset this parameter to Enable The use of all zero subnet addresses is discouraged for the following reason if an
251. s between peers 1 1 1 1 and 1 1 1 2 Display the BGP routes for either AS 123 or 456 Refer to the Cisco and Nortel Networks regular expression tables at the end of this appendix for information about the arguments that are available for these commands Show a summary of BGP global parameters Reset a neighbor s BGP connection Display BGP updates changes as they occur Show any BGP errors Display the IP routing table 308628 14 00 Rev 00 C 9 Configuring IP Exterior Gateway Protocols BGP and EGP 17 Discover the routes the router s packets take when traveling to destination 1 1 1 1 Other operational differences include the following e Cisco once peering to a neighbor is established All incoming BGP routes are accepted by default and announced too and put into IP routing table e Nortel Networks once peering to a neighbor is established All incoming BGP routes are ignored by default and not put into IP routing table e No BGP routes are advertised by default Direct connect interfaces and static routes are advertised in the BGP context when BGP Announce Policy Action parameter is set to announce and all other parameters are set to default values C 10 308628 14 00 Rev 00 Translating Cisco to Nortel Networks Equivalents Comparing BGP Route Selection Processes Table C 3 compares the Cisco and Nortel Networks path or best route selection processes In this table the most preferable criteria
252. s parameter BGP peer 3 2 A 11 in multiple RR cluster configuration 8 8 in peer to peer session definition 6 3 in route reflector cluster configuration 8 6 in RR client configuration 8 11 in single route reflector configuration 8 4 Local AS parameter BGP 3 2 A 2 Local AS to Advertise to Peer parameter 6 14 A 15 Local Autonomous System ID parameter 3 5 10 7 A 24 Local Pref Calculation parameter 5 29 Local Preference attribute calculating 5 27 local as command 5 5 local pref calculation command 5 29 MAC Address parameter adjacent host A 55 IP interface A 35 Mask parameter IP interface A 30 Max BGP Version parameter 6 7 A 12 Maximum Policy Rules parameter A 49 max update size command 6 15 max version command 6 6 Md5 Tcp Authentication BGP parameter A 17 Tcp Md5 Key BGP parameter A 19 Tcp Md5 Key Storage BGP parameter A 18 MDS authentication configuring 5 23 Message Level parameter 5 30 A 23 Message Trace Switch parameter 5 30 A 23 Min AS Origination Interval parameter 6 13 A 15 Index 4 Min BGP Version parameter 6 7 A 12 min originate time command 6 12 min version command 6 6 MTU Discovery parameter A 32 multi hop command 5 12 Multi hop EBGP Connection parameter 5 12 A 5 Multiple Nexthop Calculation Method parameter 4 7 A 49 N negotiating the BGP version 6 6 Next Hop Addr parameter 4 13 A 52 Next Hop Interface Addr parameter A 54 Next Hop Mas
253. s the speed with which IP software can learn routes because it removes the overhead caused by dynamic memory allocation Set to the number of hosts that you expect Avoid using a number that is excessively large This will cause a wasteful overallocation of memory If you use the default value 0 IP software preallocates memory for 500 routing table entries 1 3 6 1 4 1 18 3 5 3 2 1 1 13 Enable Default Route for Subnets Configuration Manager gt Protocols gt IP gt Global Disable Enable Disable Specifies whether the IP router uses a default route for unknown subnets The default route must be present in the routing table When you set this parameter to Enable the IP router uses a default route When you set this parameter to Disable the IP router does not use a default route Accept the default Disable if you do not want the IP router to use a default route for unknown subnets Otherwise reset this parameter to Enable 1 3 6 1 4 1 18 3 5 3 2 1 1 14 A 48 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Maximum Policy Rules Configuration Manager gt Protocols gt IP gt Global 32 Any integer Specifies the maximum number of policy rules that can be configured per po
254. sabled Disables BayRS local preference calculation of received EBGP routes Set this parameter as required 1 3 6 1 4 1 18 3 5 3 2 5 1 1 27 Confederation ID Configuration Manager gt Protocols gt IP gt BGP gt BGP Global 0 Any valid confederation identifier Specifies the BGP confederation identifier for this router Set this parameter to the confederation identifier of this router If this autonomous system is not a member of any confederation this parameter is not available nil 1 3 6 1 4 1 18 3 5 3 2 5 1 1 28 A 8 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Confederation Peer Configuration Manager gt Protocols gt IP gt BGP gt BGP Global List The peer list of this BGP speaker to other member sub ASs within the same confederation If this value is unavailable nil no peer exists from this speaker to neighbor ASs that are members of this local confederation Specifies the peer lists of this BGP speaker that is its peers in other member sub ASs within the same confederation Set this parameter as required 1 3 6 1 4 1 18 3 5 3 2 5 1 1 29 BGP IGP Interaction Control Configuration Manager gt Protocols gt IP gt BGP gt BGP Global 0 no interaction No interaction IGBP to RIP IGBP to OSPF Specifies whether you
255. sociated address has gone down IP uses the first available interface Use the alternate unnumbered address option to ensure that the unnumbered interface has a usable associated address on the router 1 3 6 1 4 1 18 3 5 3 2 1 24 1 111 ATM ARP Mode Configuration Manager gt Protocols gt IP gt Interfaces Client Client Server Specifies whether the router is running as an ATM client or server on this interface You must configure one ATMARP server for each logical IP subnet you define 1 3 6 1 4 1 18 3 5 3 2 1 24 1 112 ARP Server ATM Address Network Prefix Configuration Manager gt Protocols gt IP gt Interfaces None XX000000000000000000000000 to XXPFFFFFFFFFFFFFFFFFFFFFF where XX 39 45 or 47 Defines the ATM address network prefix of the ATMARP server on your network Enter the ATM address network prefix of the ATMARP server on your network A complete ATM address consists of a network prefix and a user part Use the ARP Server ATM Address User Part parameter to supply the user part of the ATM address 1 3 6 1 4 1 18 3 5 3 2 1 24 1 113 A 42 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters ARP Server ATM Address User Part Configuration Manager gt
256. speaker or peer based on local configuration information You can establish a BGP peer to peer session by setting the BGP parameters as described under the following topics Topic Page Defining a Peer to Peer Session 6 2 Initiating a Peer to Peer Session 6 4 Negotiating the BGP Version 6 6 Keeping the Connection Alive 6 7 Setting the External Advertisement Timer 6 9 Specifying a Holddown Time 6 10 Setting a Minimum AS Origination Interval 6 12 Overriding the Local AS Number 6 14 Specifying a Maximum Update Size 6 14 Setting the Route Echo Switch 6 16 Disabling and Reenabling Loop Detection 6 17 Specifying the Route Reflector Mode of the Remote Peer 6 18 Configuring Peers over an Unnumbered Point to Point Link 6 19 Assigning Weight and Class Values to an AS 6 21 308628 14 00 Rev 00 6 1 Configuring IP Exterior Gateway Protocols BGP and EGP Defining a Peer to Peer Session To define a peer to peer session you specify the following e Local IP interface address e Remote IP interface address e AS number of the autonomous system in which the remote BGP peer is located In situations where BGP speakers reside on routers that have multiple network connections over multiple IP interfaces the typical case for IBGP speakers consider using the address of the router s circuitless IP interface as the local peer address In this way you ensure that BGP is reachable as long as there
257. speaker that establishes a peer to peer session with a single external BGP speaker is a stub AS The BGP speaker provides external route information only for the networks contained within its own AS Interior BGP Routing Nortel Networks implements Interior BGP IBGP intra AS routing Under IBGP each router in the AS runs an interior gateway protocol IGP such as OSPF for internal routing updates and also maintains an IBGP connection to each BGP border router The IBGP information along with the IGP route to the originating BGP border router determines the next hop to use for external networks The IGP carries no BGP information Each router uses IBGP exclusively to determine reachability to external networks When an IBGP update for a network is received it can be passed on to IP for inclusion in the routing table only if a viable IGP route to the correct border gateway is available An AS with more than one BGP speaker can use IBGP to provide a transit service for networks outside the AS An AS that provides such a service for BGP speakers is known as a transit AS see Figure 1 3 1 6 308628 14 00 Rev 00 Exterior Gateway Protocols BGP EGP IP0021A Figure 1 3 Transit AS In Figure 1 3 AS 20 is the transit AS It provides information about its internal networks as well as t
258. static routes to the circuitless interface of the BGP router in AS 2 One ECMP route uses interface 1 the other route uses interface 2 Assume also that the two EBGP speakers have established a peer to peer session using their circuitless IP interfaces 9 6 308628 14 00 Rev 00 Configuring Route and Traffic Load Balancing Now assume that the local EBGP speaker has received from its remote peer advertisements for routes to three destinations destination_1 destination_2 and destination_3 If you configure the local EBGP speaker for ECMP route balancing BGP submits one BGP route to the routing table for each BGP destination using in turn round robin the available ECMP routes as follows 1 BGP submits a BGP route to destination_1 and specifies interface 1 as the next hop 2 BGP submits a BGP route to destination_2 and specifies interface 2 as the next hop 3 BGP submits a BGP route to destination_3 and specifies interface 1 as the next hop If you configure EBGP for traffic balancing BGP submits multiple BGP routes one for each static ECMP route in the following manner 1 BGP submits two routes to destination_1 One route specifies interface 1 the second route specifies interface 2 2 BGP submits two IP routes to destination_2 One route specifies interface 1 the second route specifies interface 2 3 BGP submits two IP routes to destination_3 One route specifies interface 1 the second route specifies int
259. t Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies An empty list A list of IP addresses Specifies one or more BGP peers This policy applies to BGP advertisements from the peers on this list To indicate that this policy applies to BGP advertisements from any BGP peer use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 7 1 11 Originating AS Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies An empty list A list of autonomous system numbers Specifies one or more autonomous systems This policy applies to BGP advertisements that originate from the ASs on this list To indicate that the policy applies to BGP advertisements originating from any AS use the default empty list 1 3 6 1 4 1 18 3 5 3 2 6 7 1 12 B 10 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Routing Policies Route Origin Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Accept Policies Any Any IGP EGP IGP or EGP Incomplete Incomplete or IGP Incomplete or EGP Specifies the values of the BGP origin path attribute that apply to this policy Select the origin values you want to accept for this policy 1 3 6 1 4 1 1
260. t ID External Route Source Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies Any Direct Static RIP OSPF with Type 2 metric EGP BGP Any Specifies one or more external route source identifiers If you specify an external route source a route from that source that meets the other criteria of this policy matches the policy This parameter applies only to OSPF routes that use the new ASE Type 2 metric The protocol from which OSPF received the route is encoded in the ASE metric along with the route s metric To specify any external route source use the default EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 9 308628 14 00 Rev 00 B 41 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID EGP Peer List Configuration Manager gt Protocols gt IP gt Policy Filters gt EGP gt Announce Policies An empty list A list of IP addresses Specifies a list of IP addresses of EGP peers If a peer appears in this list the policy applies to EGP advertisements sent to that peer Specify one or more IP addresses Use the default empty list to indicate that the policy applies to any BGP peer EGP 1 3 6 1 4 1 18 3 5 3 2 6 6 1 22 EGP
261. t and Announce Policies For example the following command specifies override as the method for accept policy pol_1 set bgp accept pol_1 med method override set bgp accept pol_1l Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Accept Policies The BGP4 Accept Policy Filters window opens 6 Click on the policy that you want to modify Edit one or more of the parameters for that policy Click on Help or see the parameter descriptions beginning on page B 13 8 Click on Done You return to the Configuration Manager window 308628 14 00 Rev 00 7 7 Configuring IP Exterior Gateway Protocols BGP and EGP Specifying Matching Criteria for a BGP Accept Policy You can use the BCC or Site Manager to specify a match for a policy Using the BCC Navigate to the policy specific prompt and enter match A match prompt appears for the policy For example accept pol_1 bgp match match bgp accept pol_l To supply matching criteria for an accept policy enter lt match_parameter gt lt value gt match_parameter value is one of the parameter value pairs described in Table 7 3 7 8 308628 14 00 Rev 00 Table 7 3 Configuring BGP
262. t share a numbered subnet each BGP peer needs to know a route to the network subnet of the interface that the other BGP peer uses If there is an IGP protocol RIP or OSPF running over the unnumbered link RIP or OSPF will learn the route and store it in the routing table Otherwise you need to configure a static route on each router to the other BGP peer s network subnet The route should point to the unnumbered link Configure the BGP connection on each router 6 20 308628 14 00 Rev 00 Establishing a Peer to Peer Session Assigning Weight and Class Values to an AS You can assign a weight class to any AS number and a weight value to a weight class Weights provide a way either to prefer or to avoid routes that pass through certain ASs The weights of each AS in a path are added and the path with the smallest total weight is the preferred path An assigned weight can range from 1 to 15 plus an infinity value Any path containing an AS weight of infinity is avoided AS weight classes allow you to assign multiple weight values to the same AS This feature allows you to consider an AS path differently for different networks For example consider a situation in which two networks 192 32 1 0 and 192 32 2 0 are both reachable by two paths The first path to each network shares a common AS AS 5 The second path to each network also shares a common AS AS 10 If you want to favor AS 5 in the path to 192 32 1 0 and AS 10 in the p
263. t specific prior written permission SUCH PORTIONS OF THE SOFTWARE ARE PROVIDED AS IS AND WITHOUT ANY EXPRESS OR IMPLIED WARRANTIES INCLUDING WITHOUT LIMITATION THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE In addition the program and information contained herein are licensed only pursuant to a license agreement that contains restrictions on use and disclosure that may incorporate by reference certain limitations and notices imposed by third parties Nortel Networks NA Inc Software License Agreement NOTICE Please carefully read this license agreement before copying or using the accompanying software or installing the hardware unit with pre enabled software each of which is referred to as Software in this Agreement BY COPYING OR USING THE SOFTWARE YOU ACCEPT ALL OF THE TERMS AND CONDITIONS OF THIS LICENSE AGREEMENT THE TERMS EXPRESSED IN THIS AGREEMENT ARE THE ONLY TERMS UNDER WHICH NORTEL NETWORKS WILL PERMIT YOU TO USE THE SOFTWARE If you do not accept these terms and conditions return the product unused and in the original shipping container within 30 days of purchase to obtain a credit for the full purchase price ji 308628 14 00 Rev 00 1 License Grant Nortel Networks NA Inc Nortel Networks grants the end user of the Software Licensee a personal nonexclusive nontransferable license a to use the Software either on a single computer or if applicable on a s
264. te source a route from that source that meets the other criteria of this policy matches the policy This parameter applies only to OSPF external routes that use the new ASE Type 2 metric The protocol from which OSPF received the route is encoded in the ASE metric along with the route s metric To specify any external route source use the default BGP 3 1 3 6 1 4 1 18 3 5 3 2 6 8 1 9 Outbound Peer AS List Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies An empty list A list of AS numbers Specifies a list of autonomous system numbers If an AS number is included in this list this policy applies to BGP advertisements being sent to BGP peers in that AS Specify one or more AS numbers Use the default empty list to indicate that this policy applies to BGP advertisements going to peers in any AS 1 3 6 1 4 1 18 3 5 3 2 6 8 1 22 308628 14 00 Rev 00 B 43 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Outbound Peers Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 3 gt Announce Policies An empty list A list of IP numbers Specifies the IP address of one or more BGP peers If a BGP peer is included in this list this policy applies to BGP advertisements being sent to that
265. ted the value of the NPK is used to encrypt the Tep Md5 Key value Enter a 16 digit hexadecimal value Enter the prefix Ox before the 16 digits This value is configurable with the WEP Key Manager gt NPK Manager or with the secure shell of the Technician Interface as described in Configuring IPsec Services None Available A 18 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Tcp Md5 Key Configuration Manager gt Protocols gt IP gt BGP gt Peers Not used if Tcp Authentication is None or if Tep Md5 Key Storage is Clear Text No default if Tep Md5 Key Storage is Encrypted ASCII character string Specifies the key to use for MD5 authentication The parameter value you specify is stored in the format specified in the Tcp Md5 Key Storage parameter Specify the value you want to use for the MD5 authentication key 1 3 6 1 4 1 18 3 5 3 2 5 1 2 1 47 BGP AS Weight and Weight Class Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID AS Configuration Manager gt Protocols gt IP gt BGP gt Weights Null 1 to 65 535 Identifies the autonomous system to which you want to assign a weight Enter the appropriate AS number 1 3 6 1 4 1 18 3 5 3 2 5 1 3 1 4 Weight Value 1 Configuration Manager gt Protocols
266. ter the preference as weight class class 1 to class 8 Indicates which weight class value should be used when calculating the AS path weight route damping enabled disabled default Configures BGP to perform route flap dampening on a route that matches this policy route damping template default or a unique template name Configures BGP to use the default route flap dampening template or the template you specify 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window The Protocols menu opens choose Protocols 2 Choose IP The IP menu opens 3 Choose Policy Filters The Policy Filters menu opens 4 Choose BGP 4 The BGP 4 menu opens 5 Choose Accept Policies The BGP4 Accept Policy Filters window opens 6 Click on Add The BGP4 Accept IP Policy Filter Configuration window opens 7 Set the following parameters Name Networks Action Route Preference Rule Precedence BGP 4 Preference AS Weight Class Click on Help or see the parameter descriptions beginning on page B 3 8 Click on OK Site Manager returns you to the BGP4 Accept Policy Filters window 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Supplying Modification Values for a BGP Accept Policy You can use the
267. ther reflectors Figure 8 1 for example shows an AS with a single route reflector connected to five IBGP speakers configured as RR clients The RR receives a route advertisement from RR client 1 determines that the route is the best route to the external destination and forwards the route to RR clients 2 3 4 and 5 RR client 2 RR client 1 y y RR client 4 RR client 3 lt q RR client 5 Autonomous system Key lt lt Peer to peer session BGP route advertisement IP0065A Figure 8 1 IBGP Single Route Reflector Topology 8 2 308628 14 00 Rev 00 Configuring a Route Reflector You configure an IBGP speaker as a route reflector by establishing a peer to peer session with an RR client You can do this with the BCC or Site Manager Using the BCC Navigate to the global BGP prompt and enter peer local lt reflector_address gt remote lt client_address gt as lt as_number gt reflector_address is the IP address of the local route reflector client_address is the IP address of the remote RR client as_number is an integer identifying the AS in which the remote client is located Because the reflector and the client are located in the same AS BGP recognizes that this is an IBGP session For complete
268. tifier Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Null 1 to 4294967295 Associates the IBGP route reflector with a cluster If this BGP router is configured as an IBGP route reflector in a cluster you must specify a cluster ID All IBGP route reflectors in the same cluster must have the same cluster ID 1 3 6 1 4 1 18 3 5 3 2 5 1 1 18 A 6 308628 14 00 Rev 00 Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Site Manager Parameters Aggregate Subnets Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Enable Enable Disable Specifies whether subnet routes from non BGP sources are aggregated to their corresponding natural network routes for advertisement to BGP peers Advertisement of BGP originated routes is not affected by this switch Set this parameter as required 1 3 6 1 4 1 18 3 5 3 2 5 1 1 22 Black Hole Routes Configuration Manager gt Protocols gt IP gt BGP gt BGP Global Disabled Disabled Drop Reject Specifies whether BGP submits a black hole route into the routing table for an aggregate route advertised to a BGP peer To prevent BGP from submitting a black hole route into the IP routing table for a route advertised to a BGP peer set this parameter t
269. to Match accept B 12 B 17 BGP Communities to Match announce B 46 BGP Communities to match announce B 53 BGP Community attribute action accept B 18 BGP Community attribute action announce B 53 BGP Community to accept accept B 18 BGP Community to announce announce B 52 BGP 3 Route Preference accept B 11 BGP 4 Preference accept B 16 EGP Interface List announce B 42 EGP Metric announce B 42 EGP Peer List announce B 42 Enable accept B 2 Enable announce B 24 External Route Source announce B 41 B 43 B 47 From BGP Peer announce B 39 From BGP Peer AS announce B 40 From EGP Peer announce B 36 From OSPF Router ID announce B 33 From RIP Gateway announce B 31 Gateway List accept B 8 Injection List accept B 9 B 13 Inter AS Metric Selector announce B 44 308628 14 00 Rev 00 Local Preference accept B 16 Local Preference Override announce B 50 Local Preference Value announce B 51 Multi Exit Discriminator announce B 48 Multi Exit Discriminator Value announce B 49 Multi Exit Discriminator accept B 19 Multi Exit Discriminator Value accept B 20 Name accept B 3 Name announce B 25 Networks accept B 4 Networks announce B 26 Next Hop announce B 51 Origin announce B 45 B 49 Originating AS accept B 10 B 14 Outbound Peer AS announce B 47 Outbound Peer AS List announce B 43 Outbound Peers announce B 44 B 48 Peer Address accept
270. tribute Choose the route with the lower interior cost to the next hop Choose external BGP over IBGP Choose the route with the lower BGP identifier Choose the route with the lower BGP connection remote address Choose the route with the lower BGP connection local address Using the BCC 10 If the next hop is inaccessible do not consider it Consider larger BGP administrative weights first If the routers have the same weight consider the route with the highest local preference If the routes have the same local preference prefer the route that the local router originated If no route was locally originated prefer the shorter AS path If the routes have the same AS path length prefer the lowest origin code IGP is preferred over EGP which is preferred over incomplete If the origin codes are the same and all paths come from the AS prefer the path with the lowest multiexit discriminator MED metric Treat a missing MED metric as 0 If the MED metrics are the same prefer external paths over internal paths If IGP synchronization is disabled and only internal paths remain prefer the path through the closest neighbor Prefer the route with the lowest IP address value for the BGP router ID Navigate to the BGP global prompt and enter local pref calculation lt siate gt state is one of the values shown in Table 5 5 5 28 308628 14 00 Rev 00 Configuring and Customizing BGP Table
271. u want the local EGP neighbor to be the initiator of EGP connections Otherwise accept the default value Passive 1 3 6 1 4 1 18 3 5 3 2 4 3 1 7 Poll Mode Configuration Manager gt Protocols gt IP gt EGP gt Neighbors Both Active Passive Both Specifies the type of neighbor reachability algorithm this local EGP neighbor executes In the active mode a router sends hello and poll messages to request reachability status from its neighbor In the passive mode a router responds to hello and poll messages with I H U and update messages Accept the default value Both or set to either Active or Passive depending on the neighbor reachability algorithm you want this router to execute 1 3 6 1 4 1 18 3 5 3 2 4 3 1 8 A 26 308628 14 00 Rev 00 Site Manager Parameters Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Hello Timer Configuration Manager gt Protocols gt IP gt EGP gt Neighbors 60 seconds 30 to 120 seconds Specifies the number of seconds between the local EGP neighbor s EGP Hello message retransmissions This variable represents the RFC 904 T1 timer Accept the default value of 60 seconds for this parameter or set it to some value from 30 to 120 seconds 1 3 6 1 4 1 18 3 5 3 2 4 3 1 9 Poll Timer Configuration Manager gt Protocols gt IP gt EGP gt Neighbors 180 seco
272. udes the AS in that position For example the expression 200 means that the policy applies to all routes whose AS_PATH attribute contains AS 200 as the last AS in the path 1 3 6 1 4 1 18 3 5 3 2 6 9 1 19 BGP Communities to Match Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of BGP communities Specifies one or more BGP communities This policy applies to all BGP advertisements that match the list Supply an octet string using the following format each community ID is 4 bytes long 0 in the two most significant bits causes the router to perform the match on the lower 16 bits the default empty list means match any list 1 3 6 1 4 1 18 3 5 3 2 6 9 1 20 AS Prepend Configuration Manager gt Protocols gt IP gt Policy Filters gt BGP 4 gt Accept Policies An empty list A list of autonomous systems Specifies one or more AS numbers to be added as a SEQUENCE to AS Path Supply an octet string containing AS numbers to be added as a SEQUENCE to AS Path 1 3 6 1 4 1 18 3 5 3 2 6 9 1 23 308628 14 00 Rev 00 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID BGP Community to accept
273. uires EGP neighbors e Determines neighbor reachability e Exchanges network reachability information with its neighbors Each of these capabilities has an associated phase in EGP the neighbor acquisition phase the neighbor reachability phase and the network reachability phase respectively In the acquisition phase EGP is responsible for forming neighbor relationships between routers that are peers Routers that are peers each have an interface to a common network One router attempts to acquire a peer router If the peer agrees to be acquired the two routers form a neighbor relationship They then negotiate the mode of operation and the polling modes After two routers agree to form a neighbor relationship they must then negotiate modes According to EGP the routers modes are determined as shown in Table 10 1 Table 10 1 Router Mode Determinator Router A Router B Resulting Modes Active Passive Router A is active Router B is passive Passive Passive Not allowed at least one router must be active Active Active The router with the lower autonomous system number becomes active the other becomes the passive router Both Active Router A is passive Router B is active Both Passive Router A is active Router B is passive Both Both The router with the lower autonomous system number becomes active the other becomes the passive router Table 10 1 shows all possible acquisition mode combinations th
274. update message with the following additions e In place of the unreachable attribute that BGP 3 includes as part of the path attribute description the BGP 4 update includes an unreachable field This field specifies destinations that have become unreachable e In place of the BGP 3 optional attributes a BGP 4 update message can include the optional attributes described in Table 1 2 Table 1 2 BGP 4 Optional Path Attributes Attribute Description Multiexit discriminator Chooses between paths to the destinations listed Local preference Allows AS border routers to indicate the preference they have assigned to a chosen route when advertising it to IBGP peers continued 308628 14 00 Rev 00 1 9 Configuring IP Exterior Gateway Protocols BGP and EGP Table 1 2 BGP 4 Optional Path Attributes continued Attribute Description Atomic aggregate Ensures that certain network layer reachability information NLRI is not deaggregated Aggregator Identifies which AS performed the most recent route aggregation The attribute contains the last AS number that formed the aggregate route followed by the IP address of the BGP speaker that formed the aggregate route Route clusters Lists the route clusters that may be traversed to reach a given destination Advertiser Identifies which border router injected the route BGP community Identifies the communities to which the route belongs A community
275. updates sent on the peer session established between interfaces 2 2 2 2 and 2 2 2 5 peer 2 2 2 2 2 2 2 5 5 max update size 950 peer 2 2 2 2 2 2 2 5 5 Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Click on the IP interface for which you want to edit BGP peer parameters 2 Choose IP The IP menu opens 3 Choose BGP The BGP menu opens 4 Choose Peers The IP Interface List for BGP window opens 6 Click on BGP Peers The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window Set the Peer Max Update Size parameter Click on Help or see the parameter description on page A 15 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window 308628 14 00 Rev 00 6 15 Configuring IP Exterior Gateway Protocols BGP and EGP Setting the Route Echo Switch The peer route echo switch controls the way the router echoes a BGP route that is chosen for forwarding Echoing in this case means advertising the route back to the peer from which it was received By default the router advertises the route back as reachable and includes the local AS You can use the BCC or Site Manager to configure BGP to echo the route as unrea
276. uter adds this MD5 signature to the TCP packet containing a BGP message and sends it with the packet but it does not send the secret key The receiver of the TCP packet also knows the secret key and can verify the MD5 signature A third party trying to masquerade as the sender however cannot generate an authentic signature because it does not know the secret key Configurations can concurrently have BGP peers with authentication enabled and authentication disabled The per peer secret keys provide the security Peers configured with common secret keys can authenticate each other and exchange routing information If the keys are compromised for example by transfer of the configuration file then the authentication itself is compromised To prevent this the secret keys can be stored in encrypted form in the configuration file and MIB using the Technician Interface secure shell to encrypt the per peer secret keys The secure shell uses DES to encrypt the secret keys and the DES key the NPK MEK is stored in the router s nonvolatile RAM NVRAM The Node Protection Key Message Encryption Key NPK MEK is configured using the Technician Interface secure shell or the Site Manager WEP Key Manager The TCP MDS secret keys can optionally be similarly encrypted Entering and Storing MD5 Authentication Keys To configure BGP TCP MD5 authentication set the wfBgpPeerTcpAuthentication MIB object to MDS You can then enter an optional variable length A
277. uters 1 1 1 1 and 2 2 2 2 to peer group MyPeers Nortel Networks handles the peer group concept by specifying the peer routers and AS in the similar AdvertiseMap announce policy and FilterMap accept policy Advertise the aggregate address 195 89 8 0 mask 255 255 248 0 195 89 8 0 21 as well as the more specific addresses i e 195 89 8 0 195 89 15 0 Advertise the aggregate address 195 89 8 0 mask 255 255 248 0 195 89 8 0 21 only To redistribute BGP routes of AS 2000 into OSPF AS 101 set Nortel Networks global OSPF parameter AS boundary Router to YES and disable BGP s Intra AS parameter To redistribute OSPF and routes of AS 101 into BGP AS 2000 set the Route Source parameter to OSPF in the router announce policy Keepalive timer is used between BGP peers as a periodic check of the TCP connection between them Holddown timer is the amount of elapsed time before the BGP peering session is declared dead RFC 1771 suggests values of 30 and 90 seconds respectively Holddown timer is suggested to be three times the amount of the keepalive timer Cisco s loopback interface and Nortel Networks circuitless IP interface is useful in BGP environments to use as peer interfaces Enable the use of subnet zero for interface addresses and routing updates Enable Confederations for IBGP full mesh reduction In this example the outside world sees this as a single AS number 5 but within the AS it is divided into autonomous systems 4001
278. vices EGP Concepte and Ter ra NG sci recsecesacipaeeisceevaete spate a a PORE EGP lmpementation NOES Seer reer ene en a a rerertnen eer 10 5 Customizing GPP 00 e ROUET senate dats pacts pac ccndaeciecGenieaiaterangeds a 10 6 Enabling and Disabling BGP rsnvinonbnicnnniaaiai ambivalent DOSS Supplying a Local AS Number PT PT aN ATN neetna OPE wetala ier PE alc te a NegNDOF casia aaa ia 10 8 Specifying the Neighbor s Address ceccceeeeceeeeeeeeeeeeeeeesaeeeeeeeeeeeeseeeteeeseaeens 10 9 Specifying the Gateway Mode 00 re cues iaa cans 10 10 Enabling and Disabling the Neighbor Relationship cccceeeeeesseeeeeeeseeeeeeeeeee 10 11 Choosing the Acquisition Mode cc ccscicscsnncsssnerecssssocunevsscnusewanscasuncsscansnacisoasine 10 12 Choosing the Pall MOGE semirsa a aa 10 13 geting NenhDOr Dl LO s dome pee ere ert Pree Ter ree scr rye rrrerrnyr rer peer verter reece er 10 14 Appendix A Site Manager Parameters BOP PaaS cantante ain ai cae A 1 BGP Cnn alah Parameters siensia eiiaoe ania AANE a A 2 BGP Global ParAinelers soricei aa a a ones A 2 BGPS GOVA PAT digia nna a a A 10 BGP 4 Global Parameter Serna P PE aman ER RT P A 10 BGP Poer PRAISING sarsie REE E Ei A 10 BGP AS Weight and Weight Class Parameters ccccccccseeeseseeeeeteeeteeeeesaees A 19 BGP Event Message Parameters aa T re eee ere E T asee A22 EGP Parmo saiaittainetiavani aid eed dane ene A 24 EGP GIODA Boel cic obs
279. with a higher metric takes precedence over a policy with a lower metric In case of a tie the protocol uses an internal index value assigned to the policy by IP software In general the index value is indicated by the position of the policy in the Site Manager display the last policy in the display has the highest index value Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager window choose Protocols The Protocols menu opens Choose IP The IP menu opens Choose Policy Filters Choose BGP 4 The Policy Filters menu opens The BGP 4 menu opens ay AJV N Choose Announce Policies The BGP4 Announce Policy Filters window opens Click on Add The BGP4 Announce IP Policy Filter Configuration window opens continued 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Site Manager Procedure continued You do this System responds 7 Set the following parameters Name Networks Action Rule Precedence e Route Source Advertise From RIP Gateway Received on RIP Interface From OSPF Router ID Received OSPF Type Received OSPF Tag From EGP Peer From EGP AS From EGP Gateway From BGP Peer From BGP AS Received BGP Next Hop External Route Source Outbound Peer AS Outbound Peers e Multi Exit Discriminator Multi Exit Discriminator Value Ori
280. y 7 2 Supplying Modification Values for a BGP Accept Policy 7 6 Specifying Matching Criteria for a BGP Accept Policy 7 8 Defining a BGP Announce Policy 7 11 Supplying Modification Values for a BGP Announce Policy 7 14 Specifying Matching Criteria for a BGP Announce Policy 7 18 Configuring BGP 4 AS Pattern Matching 7 24 Defining a BGP Accept Policy BGP accept policies govern which routes BGP submits to the IP routing table manager When BGP encounters an update that matches the policy it performs the action you specify To define a new BGP accept policy you must do the following e Supply a name for the accept policy e Set the state of the policy enabled or disabled e Specify whether BGP ignores or accepts an update that matches the policy e Rank the policy according to preference precedence and BGP weight class You can use the BCC or Site Manager to define a BGP accept policy 7 2 308628 14 00 Rev 00 Configuring BGP Accept and Announce Policies Using the BCC Navigate to the BGP global prompt and enter accept lt policy_name gt policy_name is a unique name for the BGP accept policy A policy specific prompt appears indicating that the BCC has created the policy using default values for all parameters For example the following command creates an accept policy named accept_pol_1 bgp accept accept_pol_1 accept accept_pol_1 bgp In response to the prompt enter lt parameter gt lt value gt
281. you The BGP Peer List window opens 7 Click on the peer for which you want to edit parameters The parameters for that peer appear in the window Set the following parameters Min BGP Version Max BGP Version Click on Help or see the parameter descriptions starting on page A 12 Click on Apply and then click on Done Site Manager returns you to the IP Interface List for BGP window Keeping the Connection Alive After a session has been established BGP peers periodically issue keepalive messages to maintain the connection By default BGP issues a keepalive message every 30 seconds You can use the BCC or Site Manager to specify how often BGP issues a keepalive message on this peer to peer session or to disable the keepalive function by setting the value to 0 308628 14 00 Rev 00 6 7 Configuring IP Exterior Gateway Protocols BGP and EGP Using the BCC Navigate to a BGP peer prompt and enter keepalive lt seconds gt seconds indicates how often BGP sends a keepalive message on this peer session Setting this value to 0 disables the sending of keepalive messages For example the following command causes BGP to send a keepalive message every 10 seconds on interface 2 2 2 2 to the peer at 2 2 2 5 peer 2 2 2 2 2 2 2 5 5 keepalive 10 peer 2 2 2 2 2 2 2 5 5 Using Site Manager Site Manager Procedure You do this System responds 1 In the Configuration Manager wi
282. you see the wfIpInterfaceCacheMisses statistic going up at an alarming rate you should consider increasing the table size However an occasional cache miss does not warrant an increase in table size MIB Object ID 1 3 6 1 4 1 18 3 5 3 2 1 24 1 104 Parameter Enable Security Path Configuration Manager gt Protocols gt IP gt Interfaces Default Disable Options Enable Disable Function Specifies whether Revised IP Security Option RIPSO is enabled for the interface Instructions If you do not support RIPSO on your network simply accept the default setting Disable If you are configuring RISPO support set this parameter to Enable Once you set this parameter to Enable you can access the rest of the RIPSO parameters If you do not enable this parameter Site Manager does not activate the RIPSO parameters MIB Object ID 1 3 6 1 4 1 18 3 5 3 2 1 24 1 28 308628 14 00 Rev 00 A 41 Configuring IP Exterior Gateway Protocols BGP and EGP Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Parameter Path Default Options Function Instructions MIB Object ID Unnumbered Associated Alternate Configuration Manager gt Protocols gt IP gt Interfaces Disable Enable Disable Automatically assigns an alternate associated address to an unnumbered interface in the event that the primary as
283. your hardware or software product Using Adobe Acrobat Reader you can open the manuals and release notes search for the sections you need and print them on most standard printers You can download Acrobat Reader free from the Adobe Systems Web site www adobe com You can purchase selected documentation sets CDs and technical publications through the collateral catalog The catalog is located on the World Wide Web at support baynetworks com catalog html and is divided into sections arranged alphabetically e The CD ROMs section lists available CDs e The Guides Books section lists books on technical topics e The Technical Manuals section lists available printed documentation sets 308628 14 00 Rev 00 xix Configuring IP Exterior Gateway Protocols BGP and EGP How to Get Help If you purchased a service contract for your Nortel Networks product from a distributor or authorized reseller contact the technical support staff for that distributor or reseller for assistance If you purchased a Nortel Networks service program contact one of the following Nortel Networks Technical Solutions Centers Technical Solutions Center Telephone Number Billerica MA 800 2LANWAN 800 252 6926 Santa Clara CA 800 2LANWAN 800 252 6926 Valbonne France 33 4 92 96 69 68 Sydney Australia 61 2 9927 8800 Tokyo Japan 81 3 5402 7041 XX 308628 14 00 Rev 00 Chapt

Avaya Configuring IP Exterior Gateway Protocols (BGP and EGP) User's Manual

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