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3Com 2500 Switch User Manual

1. Figure 3 3 Multiple Ports per Subnets with the LANplex 2500 System Because the LANplex model of bridging and routing allows several segments to be connected to the same subnet you can increase the level of segmentation in your network without having to create new subnets or assign network addresses Instead you can use additional Ethernet ports to expand your existing subnets This is in contrast to more traditional forms of bridging and routing where at most one port is connected to any subnet 3 4 CHAPTER 3 BRIDGING AND ROUTING IN THE LANPLEX SYSTEM In the traditional model if you want to increase the level of segmentation in your network you must create additional subnets and assign new network addresses to your existing hosts Bridging and Routing Models Traditional Bridging and Routing Model The way routing is implemented in the LANplex system differs from how bridging and routing usually coexist in a system Traditional Bridging and Routing Model Traditionally bridging and routing are peer entities either a packet is bridged or routed Packets belonging to recognized protocols are routed all others are bridged LANplex Bridging and Routing Model In the LANplex model the bridge and router operate hierarchically on the LANplex system routing over bridging When a packet enters the system the sy
2. CHAPTER 3 BRIDGING AND ROUTING IN THE LANPLEX SYSTEM Router FDDI Backbone Lo 3 n Engineering p puter Router Bridge Connectin g subnets to the enterprise Bridge p Lu m Marketing Bridge Sales O O gO Figure 3 1 Traditional Architecture of a Routed Network The LANplex system allows you to fit Ethernet switching capability into highly subnetworked environments When you put the LANplex system into such a network the system streamlines your network architecture and easily switches traffic between and within subnets over Ethernet and FDDI See Figure 3 2 Bridge T Bridge LJ c g o a eo LANplex in a Subnetworked Environment LANplex Router Engineering FDDI backbone LANplex un n Mar
3. AppleTalk Node Top Level Menu system ethemet interface fddi route atm aarp bridge zone ip forwarding ipx checksum b appletalk b ping snmp statistics analyzer script logout from one node to another which causes the destination node to return or echo the datagram an Echo Reply to the sender This allows you to determine whether a node is accessible before any sessions are started To ping an AppleTalk node At the Administration Console s top level menu enter appletalk ping You are prompted for a node address Enter the address of the node you want to ping If the node is accessible you receive a response Viewing Appletalk Statistics 12 13 Viewing Appletalk Statistics Displaying DDP Statistics Top Level Menu system ethemet interface fddi route b ddp atm aarp rtmp bridge zone zip ip forwarding nbp ipx checksum M appletalk ping snmp statistics analyzer script logout You can view statistics specific to the following AppleTalk protocols Datagram Delivery Protocol DDP Routing Table Maintenance Protocol RTMP Zone Information Protocol ZIP Name Binding Protocol NBP To display DDP statistics From the Administration Console top level menu enter appletalk statistics ddp The following is an example of DDP summary statistics DDP forwarding is enabled inReceives inForwards inLocals inNoRoutes 131131 113171 17906 22 inNoClients inTooShorts inToo
4. This 6 byte field contains the physical address of the destination node Destination Socket This 2 byte field contains the socket address of the packet s destination process Source Network This 4 byte field provides the source node s network number If a sending node sets this field to 0 it means the sources local network is unknown Source Node This 6 byte field contains the physical address of the source node Broadcast addresses are not allowed Source Socket This 2 byte field contains the socket address of the process that transmitted the packet Upper layer Data The data field contains information for the upper layer processes 6 6 CHAPTER 6 ROUTING WITH IPX IPX Packet Delivery Ona NetWare network the successful delivery of a packet depends both on the proper addressing of the packet and on the internetwork configuration Packet addressing is handled in the packet s Media Access Control MAC protocol header and IPX header address fields To send a packet to another node the sending node must know the complete internetwork address including the network node and socket of the destination node Once the sending node has the destination node s address it can proceed with addressing the packet However the way the MAC header of that packet is addressed depends on whether the sending and destination nodes are separated by a router See Figure 6 3 Sending Node Router Destination Node
5. bytes 5h 6m T1P 2m T1P 2m T1P 60s T1P 3m T1P 71s T1P 48s TIP 72s T1P 3m T1P 4m T1P 3m T1P 90s T1P Out Ifs Ilp Ilp Ilp Ilp Ilp Ilp Ilp Ilp Ilp Ilp Ilp Ilp Displaying the Multicast Cache 10 11 Table 10 2 describes the fields in the cache display Table 10 2 Information in the cache display Field Description Origin Mcast group CTmr Age PTmr In If Out If The source of the incoming packets Entries preceded by an angle bracket gt indicate a multicast subnetwork Entries without an angle bracket beneath the subnetwork entries are multicast routers within that subnetwork The destination multicast group Cache timer The amount of time in seconds s minutes m and hours h that a cache entry has to remain in the cache Number of seconds s minutes m or hours h that the cache entry has existed The time remaining in seconds s minutes m or hours h before another prune will be sent to prune the Spanning Tree Interface number on which that gateway is connected Traffic is expected to originate from this interface T represents the tunnel P denotes that a prune has been sent to this tunnel Set of interfaces on which the traffic will be flooded out 1 repre sents the interface 10 12 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING ADMINISTERING IPX ROUTING This chapter describes how to set up your LANplex system to use the Inte
6. IPX on port 6 VLAN 1 IPX frame does not match any defined VLAN As shown in this example when the subnet address of an IP packet does not match any subnet address of any defined IP VLAN in the system it is flooded to all of the IP VLANs that share the source switch port in this case port 6 The only way for stations that are in two different VLANs to communicate is to route between them The LANplex system supports internal routing among IP IPX and AppleTalk VLANs If VLANs are configured for other routable network layer protocols they can communicate between them only via an external router The LANplex routing model lets you configure routing protocol interfaces based on a VLAN defined for that protocol To assign a routing interface you must first create a VLAN for that protocol and then associate it with that interface For example to create an IP interface that can route through a VLAN Create an IP VLAN for a group of switch ports This IP VLAN does not need to contain layer 3 information unless you want to further restrict flooding according to the layer 3 subnet address Configure an IP interface with a network address subnet mask broadcast address cost and type VLAN Select an IP VLAN to bind to that IP interface About VLANs 2 9 If layer 3 information is provided in the IP VLAN for which you are configuring an IP interface the subnet portion of both addresses must be compatible For example IP VLAN s
7. Static Servers A static server is one you manually configure in the server information table Static servers are useful in environments where no routing protocol is used or where you want to override some of the servers generated with a routing server protocol Because static servers do not automatically change in response to network topology changes you should manually configure only a small number of relatively stable servers Dynamic Routes Using SAP An automated method of adding and removing services helps you keep up with a changing network environment allowing servers to advertise their services and addresses quickly and reliably SAP provides this automated method As servers are booted up they advertise their services using SAP When servers are brought down they use SAP to indicate that their services are no longer available The information that these servers broadcast is not directly used by clients rather it is collected by a SAP agent within each router on the server s segment The SAP agents store this information in the server information table Clients can then use the table to contact the nearest router or file server SAP agent for server information Server Information Maintenance When a router s SAP agent receives a SAP broadcast response indicating a change in the internetwork server configuration the agent must update its server information table and inform other SAP agents of these changes Examples of such a c
8. The interface prompts you to enable or disable DVM RP The default is disabled Example dvmrp mode enabled disabled disabled enabled Enabling and Disabling IGMP IGMP enables a router or switch to determine whether group members exist in a subnetwork or leaf of the Spanning Tree It uses two search methods to make this determination Query mode The router or switch with the lowest IP address in the LAN broadcasts a query to all other members of the subnetwork to determine whether they are also in the group End stations respond to the query with IGMP packets which report the multicast group to which they belong Snooping mode A router or switch performs dynamic multicast filtering based on IGMP snooping This procedure ensures that multicast packets are flooded only to the appropriate ports within a routing interface Top Level Menu System ethernet fddi atm bridge bip ipx appletalk snmp analyzer script logout interface Toute arp atmArpServ4_ interface M multicast tunnel udpHelper routeDisplay routing cacheDisplay icmpRouterDiscovery rip ping statistics Administering IP Multicast Interfaces 10 3 When you select the IGMP option the interface prompts you to enable or disable IGMP snooping mode and IGMP query mode Both are enabled by default Under most conditions IGMP snooping mode and IGMP query mode should remain enabled To enable or disable IGMP from th
9. UDP Helper ATM ARP Server for LANplex systems with ATM modules IP Routing ICMP Router Discovery Routing Information Protocol RIP Ping IP statistics Administering interfaces You can define two types of IP interfaces through LANplex Extended Switching software IP VLAN interfaces and IP LIS interfaces This section describes these interfaces and how to administer them An IP VLAN interface defines the relationship between an IP Virtual LAN VLAN and the subnets in the IP network Every IP VLAN interface has one IP VLAN associated with it Each Ethemet or FDDI switching module has one interface defined for each subnet directly connected to it You must first define a VLAN as described in Chapter 8 Administering VLANs before you define an associated IP VLAN interface 9 2 CHAPTER 9 ADMINISTERING IP ROUTING LIS Interfaces A logical IP subnet LIS interface supports logical IP over ATM You define LIS interfaces for the ports on ATM modules only See the Chapter 11 of the LANplex 2500 Operation Guide for more information about the ATM protocol See the LANplex 2500 Administration Console User Guide for information about how to configure ATM ports Interface Each IP interface has the following information associated with it Characteristics IP Address This address which is specific to your network should be chosen from the range of addresses assigned to your organization by the central agency This address defi
10. con Part No 801 00343 000 Published November 1996 Revision 02 LANPLEX 2500 EXTENDED SWITCHING USER GUIDE 3Com Corporation m 5400 Bayfront Plaza m Santa Clara California m 95052 8145 3Com Corporation 1996 All rights reserved No part of this documentation may be reproduced in any form or by any means or used to make any derivative work such as translation transformation or adaptation without permission from 3Com Corporation 3Com Corporation reserves the right to revise this documentation and to make changes in content from time to time without obligation on the part of 3Com Corporation to provide notification of such revision or change 3Com Corporation provides this documentation without warranty of any kind either implied or expressed including but not limited to the implied warranties of merchantability and fitness for a particular purpose 3Com may make improvements or changes in the product s and or the program s described in this documentation at any time UNITED STATES GOVERNMENT LEGENDS If you are a United States government agency then this documentation and the software described herein are provided to you subject to the following restricted rights For units of the Department of Defense Restricted Rights Legend Use duplication or disclosure by the Government is subject to restrictions as set forth in subparagraph c 1 ii for restricted Rights in Technical Data and Computer Software
11. interface fddi Toute display atm server static bridge forwarding remove 2 ip rip flush b ipx enhanced appletalk sap 3 snmp statistics analyzer script logout Flushing Servers Top Level Menu System ethemet interface fddi Toute display atm P server static bridge forwarding remove ip rip M flush Dipx enhanced appletalk sap snmp statistics analyzer script logout Enter the number of hops to the server Example Enter Interface number 1 Enter service type 4 Enter service name gb201 Enter IPX address 0x8c14a238 Enter socket 0x8059 Enter node address 00 00 2e f 3 56 01 Enter hops 2 To remove a server From the Administration Console top level menu enter ipx server remove Enter the service type of the server Enter the service name of the server The server is immediately deleted from the server table Flushing deletes all dynamically learned servers from the server table To flush all learned servers From the Administration Console top level menu enter ipx server flush All learned servers are immediately deleted from the server table Setting IPX Forwarding 11 11 Setting IPX You can control whether the system forwards or discards IPX packets Forwarding addressed to other routers When you enable IPX forwarding the system acts as a normal IPX router forwarding IPX packets from one network to another when required When you disable IPX for
12. However knowing how different management features are derived from the MIB allows you to better understand how to use the information that they provide CHAPTER 13 REMOTE MONITORING RMON TECHNOLOGY The LANplex system supports the following syntax for alarms counters gauges integers and timeticks These mechanisms report information about the network to the network administrator Counters for example hold and update the number of occurrences of a particular event through a port module or switch on the network Alarms monitor the counters and report instances of when counters exceed their set threshold Counters are useful when you compare their values at specific time intervals to determine rates of change The time intervals can be short or long depending on what you measure Occasionally reading counters can give you misleading results Counters are not infinite which makes rate comparisons an efficient way to use them When counters reach a predetermined limit they return to 0 roll over A single low counter value might accurately represent a condition on the network It might simply indicate that a roll over has occurred When you disable a port the application might not update some of the statistics counters associated with it An alarm calculates the difference in counter values over a set time interval and remembers the high and low values When the value of a counter exceeds a preset threshold the alarm reports t
13. It also describes how these concepts are implemented in the LANplex system Shipped with system Part No 801 00344 000 LANplex 2500 Administration Console User Guide Provides information about using the Administration Console to configure and manage your LANplex system Shipped with system Part No 801 00322 000 LANplex 2500 Extended Switching User Guide This book Describes how the routing protocols VLAN and RMON are implemented in the LANplex system and provides information about using the Administration Console to configure and manage these features shipped with the option package Part No 801 00343 000 LANplex 2500 Intelligent Switching Administration Console Command Quick Reference card Contains the Administration Console Intelligent Switching commands for the LANplex system Shipped with the system Part No 801 000318 000 LANplex 2500 Extended Switching ADMINISTRATION CONSOLE Command Quick Reference card Contains the Administration Console Extended Switching commands for the LANplex system Shipped with the option package Part No 801 00319 000 Documentation Comments 5 Provide an overview installation instructions LED status information and pin out information for the particular option module Shipped with individ a Module Installation Guides ual modules Documentation Your suggestions are very important to us and will help make our Comments documentation more useful to you Please email co
14. PARTII VIRTUAL LAN TECHNOLOGY 2 VLANSON THE LANPLEXGSYSTEM AboutVLANs 2 1 TypesofVLANs 2 1 Port Group VLANs 2 1 MAC Address Group VLANS 2 2 Application Oriented VLANS 2 2 Protocol Sensitive VLANS 2 2 LANplex Protocol Sensitive VLAN Configuration 2 3 Protocol Suite 2 3 Switch Ports 2 4 Layer 3 Addressing Information 2 4 Default VLAN 2 5 PART lll 3 Modifying the Default VLAN 2 5 How the LANplex System Makes Flooding Decisions 2 5 VLAN Exception Flooding 2 6 Overlapped IPVLANs 2 7 Routing Between VLANs 2 8 VLAN Examples 2 10 Examplel 2 10 Example2 2 11 ABOUT ROUTING PROTOCOLS BRIDGING AND ROUTING IN THE LANPLEX SYSTEM What Is Routing 3 1 LANplex in a Subnetworked Environment 3 2 Integrating Bridging and Routing 3 3 Bridging and Routing Models 3 4 Traditional Bridging and Routing Model 3 4 LANplex Bridging and Routing Model 3 6 ROUTING WITH IP TECHNOLOGY IP Routing and the OSI Model 4 1 Elements of IP Routing 4 2 IP Addresses 4 2 Address Classes 4 3 Subnet Part of an IP Address 4 3 Router Interfaces 4 4 Routing Table 4 5 Static Routes 4 6 Dynamic Routes Using RIP 4 6 Default Route 4 7 Address Resolution Protocol ARP 4 7 IP Routing Transmission Errors 4 9 Routing with Classical IP over ATM 4 10 About Logical IP Subnets LISs 4 10 ATM ARP Servers 4 10 Forwarding to Nodes within an LIS 4 11 IP Routing References 4 11 ROUTING WITH IP MULTICAST About IP Multicast Routing 5 1 IGMP 5 1 DVMRP
15. Toute udpHelper Touting icmpRouterDiscovery rip ping statistics I barp display atmArpServ remove 2 multicast flush You might want to remove an entry from the ARP cache if the MAC address has changed To remove an entry from the ARP cache From the top level of the Administration Console enter ip arp remove Enter the IP address you want to remove The address is immediately removed from the table If necessary the system subsequently uses ARP to find the new MAC address corresponding to that IP address Flushing the ARP Top Level Menu_ Cache system m ethemet interface fddi Toute am harp display bridge atmAmSen remove bip multicast flush ipx udpHelper appletalk outing snmp icmpRouterDiscovery analyzer P script ping logout statistics Administering ATM ARP Servers 9 15 You might want to delete all entries from the ARP cache if the MAC address has changed To remove all entries from the ARP cache from the top level of the Administration Console enter ip arp flush The ARP cache entries are immediately removed from the table Administering ATM ARP Servers Displaying ATM ARP Servers Top Level Menu system ethernd fddi interface am Toute arp displa ja b atmArpServ dn i multicast udpHelper applet routing snmp analyze script logout statistics rip Index If you are running classical IP over ATM with SVC
16. flushing 9 15 removing an entry from 9 14 9 19 9 20 ASP 7 10 ATM ARP cache displaying 9 17 flushing 9 18 removing an entry 9 17 ATM ARP servers about 4 10 defining 9 15 nodes that can function as an 4 10 ATP 7 9 B BOOTP relay threshold 9 20 bridge menu 1 4 bridge menu 1 3 bridging routing LANplex model 3 4 traditional model 3 4 bulletin board service A 1 C cache displaying the IP multicast 10 9 checksum configuring AppleTalk 12 12 chooser Macintosh 7 2 CompuServe A 2 conventions notice icons 2 D datagram delivery protocol 7 6 datagrams statistics 9 23 data link layer 4 1 DDP statistics 12 13 default route displayed 9 11 default route IP defined 4 7 9 10 removing 9 13 setting 9 13 defining 9 4 defining an ATM ARP 9 15 ATM ARP server 9 4 direct route status 9 10 DVMRP about 5 2 enabling 10 2 metric value 5 5 10 3 dynamic routes 4 6 6 14 See also RIP See also SAP dynamic routes IPX 6 9 extended network numbers 7 2 extended switching overview 1 1 F fax service See 3ComFacts flushing ARP cache 9 15 learned routes AppleTalk 12 6 learned routes IP 9 12 learned routes IPX 11 7 for 11 9 forwarding configuring AppleTalk 12 11 G gateway routing table and the 4 5 See also router H hysteresis mechanism 13 8 l ICMP defined 4 9 echo request and reply 9 22 echo Reply 4 9 echo request 4 9 ping and 9 22 Redirect 4 9 Time Exceeded 4 9 ICMP R
17. server table of network service information Clients on the network can determine what services are available and obtain the network address of the nodes servers where they can access those services Clients require this information to initiate a session with a file server SAP allows one router to exchange information with a neighboring SAP agent As a router s SAP agent becomes aware of any change in the network server layout it immediately broadcasts this information to any neighboring SAP agents The router also periodically sends SAP broadcast packets containing all server information known to the SAP agent These broadcasts synchronize all servers on the network and age those servers that might become inaccessible because of any abnormal shut down of the router or server 6 4 CHAPTER 6 ROUTING WITH IPX How IPX Routing Works IPX Packet Format A router operates at the network layer of the OSI Reference Model This means that it receives its instructions to route packets from one segment to another from a network layer protocol IPX with the help of RIP performs these network layer tasks These tasks include addressing routing and switching information packets to move single packets from one location to another This section first describes the information included in an IPX packet that helps it get delivered and then it describes the IPX packet delivery process The IPX packet format consists of two parts a 30 byte he
18. snmp analyzer script logout sap statistics Interface display define You might want to change the configuration of an interface that you have already defined To modify an IPX interface From the Administration Console top level menu enter ipx interface modify You are prompted for the interface parameters Press Return at the prompts for which you do not want to modify the value Modify the existing interface parameters by entering a new value at the prompt You may want to remove an interface if you no longer perform routing on the ports associated with the interface To remove an IPX interface definition From the Administration Console top level menu enter ipx interface remove Enter the index number s of the interface s you want to remove The interface is removed Administering Routes 11 5 Administering Routes Your system maintains a table of routes to other IPX networks You can either use the Routing Information Protocol RIP to exchange routing information automatically or make static entries in this table using the Administration Console Each routing table entry contains the following information Address The 4 byte IPX network address of a segment currently known to the router Hops The number of routers that must be crossed to reach the network segment The maximum number of routers a packet can cross is 15 Exception An IPX NetBIOS packet can cross no more than 7 ro
19. 25 Tl I1 Table 10 1 describes the fields in the route display Displaying the Multicast Cache 10 9 Table 10 1 Field Attributes for Multicast route display Field Description Origin Subnet The source address and the number of bits in the subnetwork From Gateway The interface address of the gateway Metric The hop count Tmr The amount of time in seconds since the routing table entry was last reset In Ifl Interface number on which that gateway is connected Traffic is expected to originate on this interface T represents the tunnel P denotes that a prune has been sent to this tunnel Out If Set of interfaces on which the traffic will be flooded out 1 repre sents the interface Tn if and Out ff Together these attributes define a Spanning Tree configuration Interfaces that comprise loops are disabled Displaying the Multicast Cache Top Level Menu System ethernet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route arp atmArpServ multicast udpHelper routeDisplay routing cacheDisplay icmpRouterDiscovery rip ping statistics dvmrp igmp interfaces tunnel 2 The IP multicast cache contains the IP source address and destination address for packets observed on the system The multicast cache shows you how information is routed over interfaces and ports in your system To display all learned routes in the multicast c
20. 5 2 TheMBONE 5 2 Multicast Routing Algorithms 5 3 Flooding 5 3 Spanning Trees 5 3 Reverse Path Forwarding 5 4 Pruning 5 5 Multicast Interfaces 5 5 DVMRP Metric Value 5 5 Time To Live TTL Threshold 5 5 Rate Limit 5 6 Multicast Tunnels 5 6 ROUTING WITH IPX IPX Routing in the NetWare Environment 6 1 Internet Packet Exchange IPX 6 2 Routing Information Protocol RIP 6 3 Service Advertising Protocol SAP 6 3 How IPX Routing Works 6 4 IPX Packet Format 6 4 IPX Packet Delivery 6 6 Sending Node s Responsibility 6 6 Router s Responsibility 6 7 The Elements of IPX Routing 6 8 Router Interfaces 6 8 Routing Tables 6 8 Generating Routing Table Information 6 9 Selecting the Best Route 6 10 Service Advertising Protocol 6 10 Internetwork Service Information 6 10 SAP Packet Structure 6 11 Server Information Table 6 13 Server Information Maintenance 6 14 PART IV 8 ROUTING IN AN APPLETALK ENVIRONMENT About AppleTalk8 7 1 AppleTalk Network Elements 7 1 AppleTalk Networks 7 2 AppleTalk Nodes 7 2 Named Entities 7 2 AppleTalk Zones 7 3 Seed Routers 7 4 AppleTalk Protocols 7 4 Physical Connectivity 7 5 The Datagram Delivery Protocol DDP 7 6 End to End Services 7 6 Transport Layer Protocols 7 6 The Session Layer Protocols 7 9 Presentation Layer 7 10 About AARP 7 10 ADMINISTERING EXTENDED SWITCHING FEATURES ADMINISTERING VLANS Displaying VLAN Information 8 1 Defining VLAN Information 8 3 Modifying VLAN Information
21. 8 4 Removing VLAN Information 8 5 ADMINISTERING IP ROUTING Administering interfaces 9 1 LIS Interfaces 9 2 Interface Characteristics 9 2 Displaying Interfaces 9 3 Defining an IP LIS Interface 9 4 Defining an IP VLAN Interface 9 6 Modifying an Interface 9 7 Removing an Interface 9 7 Adding an Advertisement Address 9 8 Removing an Advertisement Address 9 8 Adding a Permanent Virtual Circuit PVC 9 9 Removing a Permanent Virtual Circuit PVC 9 9 Administering Routes 9 9 Displaying the Routing Table 9 11 10 Defining a Static Route 9 11 Removing aRoute 9 12 Flushing a Route 9 12 Setting the Default Route 9 12 Removing the Default Route 9 13 Administering the ARP Cache 9 13 Displaying the ARP Cache 9 14 Removing an ARP Cache Entry 9 14 Flushing the ARP Cache 9 15 Administering ATM ARP Servers 9 15 Displaying ATM ARP Servers 9 15 Defining an ATM ARP Server 9 16 Removing an ATM ARP Server 9 16 Displaying the ATM ARP Cache 9 17 Removing an ATM ARP Cache Entry 9 17 Flushing the ATM ARP Cache 9 18 Administering UDP Helper 9 18 Displaying UDP Helper Information 9 19 Defining a Port and an IP Forwarding Address 9 19 Removing a Port or an IP Forwarding Address 9 19 Setting the BOOTP Hop Count Limit 9 20 Setting the BOOTP Relay Threshold 9 20 Enabling and Disabling IP Routing 9 20 Enabling and Disabling ICMP Router Discovery 9 21 Setting the RIP Mode 9 21 Pinging an IP Station 9 22 Displaying IP Statistics 9 23 AD
22. CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT ADMINISTERING VLANS oe tte eo ss This chapter describes how to display information about VLANs and how to configure VLANs Through the Administration Console you can a Display summary or detailed information on VLANs Define or modify a VLAN definition Delete a VLAN definition Displaying VLAN You can display a summary of VLAN information or a detailed report When Information you display a summary you receive information about the protocols and ports assigned to each VLAN plus the layer 3 addresses used to manage flood domains for overlapping IP subnets The detailed VLAN report includes Top Level Menu the summary information plus additional utilization statistics system themet SM a ea From the top level of the Administration Console enter atm d P bridge irritation bridge vlan summary ip ipxSnapTranslation ipx addressThreshold or appletalk agingTime snmp stpState bridge vlan detail analyzer stpPriority script stpMaxAge j j ic di j ifi b spree deal The VLAN information is displayed in the format you specified stpForwardDela sipGroupAddresy Modify Example of a summary display for several VLANS port remove ee Select menu option bridge vlan summary Index Protocol Identifier Ports t default 0 1 17 2 IP 2 Lj SEY 3 IPX 3 8 10 4 IP 4 73 12 15 CHAPTER 8 ADMINISTERING VLANS Index Name 1 none 2 eastgroup 3 w
23. LIS When you define an IP LIS interface you specify several general IP interface Top Level Menu system ethemdP interface statisti Interface characteristics and IP LIS characteristics Before you define an IP LIS interface with SVCs be sure you have defined an ATM ARP server as described in the section Administering ATM ARP Servers later in this chapter If the LIS interface has only PVCs you do not need to summary define an ATM ARP server modify To define an IP interface remove addAdvertisement ini 1 mowAdvesmey From the top level of the Administration Console enter addPVC removePVC ip interface define Co Administering interfaces 9 5 The Console prompts you for the interface s parameters To use the value in brackets press Return at the prompt 2 Enterthe IP address of the interface 3 Enter the subnet mask of the network to which the interface is to be connected 4 Enterthe cost value of the interface 5 Enterthe type of IP interface LIS 6 Enter the advertisement addresses for this interface You can enter up to 32 advertisement addresses for each interface The maximum number on the LANplex system is 64 7 Enterthe LIS information a Fora LIS interface with SVCs enter the ATM ARP server address the maximum SVC count the inactivity timer the minimum holding time and the ATM port associated with the interface You can also accept the defaults for these values a For
24. Network 000000AA Node 000000000001 Socket 4003 Network 000000BB Node 000000000003 Socket 0451 Node Node 000000000020 000000000021 MAC Header MAC Header Destination Node 000000000020 Destination Node 000000000003 Source Node 000000000001 Source Node 000000000021 IPX Header IPX Header Checksum Checksum Packet Length Packet Length Tranport Control Tranport Control Packet Type Packet Type Dest Network 000000BB Dest Network 000000BB Dest Node 000000000003 Dest Node 000000000003 Dest Socket 0451 Dest Socket 0451 Source Network 000000AA Source Network 000000AA Source Node 000000000001 Source Node 000000000001 Source Socket 4003 Source Socket 4003 Figure 6 3 IPX Packet Routing Sending Node s Responsibility When a node needs to send information to another node with the same network number the sending node can simply address and send packets directly to the destination node However if the sending and receiving nodes have different network numbers the sending node must find a router on its own network segment that can forward packets to the destination node s network segment How IPX Routing Works 6 7 To find this router the sending node broadcasts a RIP packet requesting the best route to the destination nodes network number The router residing on the sending node s segment with the shortest path to the destination segment responds to the RIP request
25. The router s response includes its network and node address in the IPX header If the sending node is a router rather than a workstation the router can get this information from its internal routing tables and need not send a RIP request Once the sending node knows the router s node address it can send packets to the destination node Router s Responsibility When a router receives an IPX packet it handles the packet in one of two ways If the packet is destined for a network number to which the router is directly connected the router performs the following tasks a Places the destination node address from the IPX header in the destination address field of the MAC header Places its own node address in the source address field of the MAC header Increments the Transport Control field of the IPX header and transmits the packet on the destination node segment If the packet is destined for a network number to which the router is not directly connected the router sends the packet to the next router along the path to the destination node as follows The router looks up the node address in the routing information table of the next router and places the address in the destination address field of the packet s MAC header For more information on routing tables see the next section The router places its own node address in the source address field of the packet s MAC header The router increments the Transport Cont
26. VPI VCI pair that you want to remove jan pp prenove Administering Each system maintains a table of routes to other IP networks subnets and Routes hosts You can make static entries in this table using the Administration Console or configure the system to use RIP to exchange routing information automatically Each routing table entry contains the following information Destination IP Address and Subnet Mask These elements define the address of the destination network subnet or host A route matches an IP address if the bits in the IP address that correspond to the bits set in the route subnet mask match the route destination address If the system finds CHAPTER 9 ADMINISTERING IP ROUTING more than one routing table entry matching an address it uses the most specific route which is the route with the most bits set in its subnet mask For example the route to a subnet within a destination network is more specific than the route to the destination network Routing Metric This metric specifies the number of networks or subnets through which a packet must pass to reach its destination This metric is included in RIP updates to allow routers to compare routing information received from different sources Gateway IP Address This address tells the router how to forward packets whose destination addresses match the route s IP address and subnet mask The system forwards such packets to the indicated gateway Status For
27. a 11 9 station See also FDDI station statistics AppleTalk viewing 12 13 IP 9 23 IPX forwarding 11 17 IPX SAP 11 16 ZIP displaying 12 15 subnet mask defined 4 3 diagram 4 4 example 4 4 in routing table 4 5 subnetting defined 4 3 Ethernet switching and 3 2 subnet mask and the 4 3 with the LANplex 3 2 T technical support A 1 ThreeComForum A 2 timing out IP route status 9 10 T notify configuring 8 4 transmission errors ICMP Redirect 4 9 reasons for 4 9 TTL threshold 5 5 IP multicast 10 3 tunnels IP multicast 5 6 10 6 V VLAN information defining 8 3 displaying 8 1 modifying 8 4 removing 8 5 VLAN interfaces about 9 1 characteristics of 9 2 defining 9 6 VLANs application oriented 2 2 MAC address group 2 2 overlapped IP 2 7 port group 2 1 protocol sensitive 2 2 routing between 2 8 Z ZIP 7 9 statistics displaying 12 15 zone information protocol ZIP 7 9 zone information table ZIT 7 9 displaying the 12 10 zone AppleTalk default 12 3 example of 7 3 naming 12 3
28. administer IP routing Chapter 9 How to administer IP mulitcast routing Chapter 10 How to administer IPX routing Chapter 11 How to administer AppleTalk routing Chapter 12 Remote Monitoring RMON Chapter 13 3Com Technical Support Appendix A Conventions Table 1 and Table 2 list conventions that are used throughout this guide Table 1 Notice Icons Icon Type Description Information Note Information notes call attention to important features or ig instructions Caution Cautions alert you to personal safety risk system damage A or loss of data Warning Warnings alert you to the risk of severe personal injury LANplex 2500 Documentation 3 Table2 Text Conventions Convention Description Enter Enter means type something then press the Retum or Enter key Syntax vs Command Syntax indicates that the general command syntax form is provided You must evaluate the syntax and supply the appropriate value for example Set the date by using the following syntax mm DD yy hh mm ss xm Command indicates that all variables in the command syntax form have been supplied and you can enter the command as shown in text for example To update the system software enter the following command system software Update screen display This typeface indicates text that appears on your terminal screen for example NetLogin commands This typeface indicates commands that you enter for example bridge
29. and 24 bits for the host part Although only a few Class A networks can be created each can contain a very large number of hosts Class B addresses have 16 bits for the network part and 16 bits for the host part Class C addresses have 24 bits for the network part and eight bits for the host part Each Class C network can contain only up to 254 hosts but many such networks can be created The class of an IP address is designated in the high order bits of the network parts of the address Subnet Part of an IP Address In some environments the IP address contains a subnet part Subnetting allows a single Class A B or C network to be further subdivided internally while still appearing as a single network to other networks The subnet part of the IP address is only visible to those hosts and gateways on the subnet network When an IP address contains a subnet part a subnet mask is used to identify which bits are the subnet address and which are the host address A subnet mask is a 32 bit number that uses the same format and representation as IP addresses Each IP address bit corresponding to alin the subnet mask is in the network or subnet part of the address Each IP address bit corresponding to a 0 is in the host part of the IP address See Figure 4 3 4 4 CHAPTER 4 ROUTING WITH IP TECHNOLOGY Router Interfaces Subnet Mask 1 jf 1 hi 1 if 1 if 1 jh 1 i t 1 jJ 1 ojo o o o o o Take the IP address IP Address Ne
30. appletalk interface display Example DDP forwarding is enabled Index Network Range Address State VLAN index 1 20112 20112 20112 27 enabled 3 2 20124 20124 20124 1 enabled 2 3 20125 20125 20125 1 enabled 4 When you define an interface you define the interface s network range zone name and the VLAN index associated with the interface You must define an AppleTalk VLAN before you define the AppleTalk interface to associate with that VLAN To define an AppleTalk interface At the Administration Console s top level menu enter appletalk interface define You are prompted for the interfaces parameters To use the value in brackets press Return at the prompt The following message appears Configure seed interface n y y Enter n no or y yes Enter the start of the network range associated with the interface Enter the end of the network range associated with the interface Enter the default zone name The default zone name is used by clients that have not been configured to use a particular zone 12 4 CHAPTER 12 ADMINISTERING APPLETALK ROUTING Removing an Interface Top Level Menu System ethemet I interface fddi route display atm aarp define bridge zone M remove ip forwarding ipx checksum appletalk ping snmp statistics analyzer script logout Enter the zone name You can enter up to 16 zone names per interface Type q after entering all the zone names Enter the index of the
31. as described in Chapter 9 Administering IP Routing before you define any IP multicast interfaces This appendix includes information on how to display or configure the following parameters Enabling and disabling the Distance Vector Multicast Routing Protocol DVMRP Enabling and disabling the Intemet Group Membership Protocol IGMP Administering IP multicast interfaces Administering multicast tunnels The Route display The Cache display To use IP multicast routing on the LANplex system you must have already defined one or more IP interfaces See Chapter 9 Administering IP Routing CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING Enabling and Disabling DVMRP Top Level Menu system ethernet fddi ipx appletalk snmp analyzer script logout interface route dvmrp igmp interfaces tunnel udpHelper routeDisplay routing cacheDisplay icmpRouterDiscovery rip ping statistics DVMRP is the simple Distance Vector Multicast Routing Protocol similar to the IP Routing Information Protocol Multicast routers exchange distance vector updates that contain lists of destinations and the distance in hops to each destination The routers maintain this information in a routing table To run multicast routing you must enable DVMRP which enables DVMRP on all IP interfaces that have not been disabled To enable or disable DVMRP from the top level of the Administration Console enter ip multicast dvmrp
32. display define remove arp multicast dvmrp igmp interfaces tunnel RouteDisplay cacheDisplay udpHelper menu isplay define remove hopCountLimit threshold Figure 1 2 IP Menu Hierarchy Using Menus 1 5 IPX Menu From the ipx menu you can view information about and configure Internet Packet Exchange IPX interfaces routes and servers You can also administer the Routing Information Protocol RIP Enhanced RIP mode Service Advertising Protocol SAP and statistics Figure 1 3 shows the IPX menu For example to define a new IPX interface enter ipx at the top level menu interface at the ipx menu and then define at the interface menu Top Level Menu ipx menu interface menu system Dinterface display ethemet b route define fddi Dserver modify atm forwarding remove bridge rip ip enhanced ipx 4 sap route menu appletalk by statistics display snmp static analyzer remove script flush logout server menu display static remove flush statistics menu summary rip sap forwarding Figure 1 3 IPX Menu Hierarchy 1 6 CHAPTER 1 LANPLEX EXTENDED SWITCHING FEATURES Appletalk Menu From the appletalk menu you can view information about and configure Appletalk interfaces routes and zones You can also administer the Appletalk Address Resolution Protocol AARP AppleTalk forwarding and statistics Figure 1 4 sho
33. in a routing entry because the hop count advertised in a routing table was equal to the current hop count for a particular network routeLessChgs Number of times RTMP changes the Next Internet Router in a routing entry because the hop count advertised in a routing table was less than the current hop count for a particular network routeDeletes Number of times RTMP deletes a route because it was aged out of the table routeOverflows Number of times RTMP attempted to add a route to the RTMP table but failed due to lack of space inVersionErrs Number of RTMP packets received that were rejected due to a version mismatch inOtherErrs Number of RTMP packets received that were rejected for an error other than due to a version mismatch To display ZIP statistics From the Administration Console top level menu enter appletalk statistics zip CHAPTER 12 ADMINISTERING APPLETALK ROUTING An example of summary statistics is shown below DDP forwarding is enabled inQueries inReplies inExReplies inGniRequests 248 14 0 182 inGniReplies inLocalZones inZoneLists 22 30 0 inObsoletes inZoneCons inZoneInvs inErrors 0 0 22 0 outQueries outReplies outExReplies outGniRequests 9 0 277 13 outGniReplies outLocalZones outZoneLists 182 0 30 outZoneInvs outAddrInvs Table 12 3 describes the ZIP statistics you can view Table 12 3 ZIP Statistics Field Description inQueries Number of ZIP queries received inReplies Number of ZIP replies recei
34. learned routes are immediately deleted from the routing table atm server static bridge forwarding remove ip rip M flush D ipx enhanced appletalk sap snmp statistics analyzer script logout 11 8 CHAPTER 11 ADMINISTERING IPX ROUTING Administering Servers Your system maintains a table of servers that reside on other IPX networks You can either use the Service Advertising Protocol SAP to exchange server information automatically or make static entries in this server table using the Administration Console Each server table contains the following information Name The user defined name of the server Type The type of service provided by the server Node The 6 byte address of the server that can forward packets to the segment Socket The 2 byte socket address on which the server will receive service requests Hop The number of networks that must be crossed to reach the server The maximum number is fifteen Age The number of seconds that have elapsed since the last time a server in the table was heard from Displaying the Server Table Top Level Menu System ethernet interface fddi Toute atm M server bridge forwarding ip rip ipx enhanced appletalk sap snmp statistics analyzer script logout M display static remove flush Interface 2 2 Defining a Static Top Level Menu System ethemet interface fddi Toute atm M server bridge forwarding i
35. messages delivered to the IPX application that were dropped due to resource limitations Displaying Statistics 11 15 Displaying IPX RIP To display IPX RIP statistics from the Administration Console top level Statistics menu enter ipx statistics rip Top Level Menu Example below System ethernet interface fddi Toute summary atm sever Brip bridge forwarding sap RIP Received ip rip forwardin Pipx enhanced 106195 appletalk Sap a P statistics RIP Responses analyzer script 100552 logout IPX forwarding is enabled RIP is active SAP is active RIP Transmitted RIP dropped 7929 0 RIP Requests RIP Entries 5643 2 Table 11 2 describers the IPX RIP statistics Table 11 2 IPX RIP Statistics Field Description RIP Received RIP Transmitted RIP Dropped RIP Responses RIP Requests RIP Entries Number of IPX RIP packets received Number of IPX RIP packets transmitted Number of IPX RIP packets dropped Number of IPX RIP responses that have been processed Number of IPX RIP requests that have been processed Number of routes in the routing table 11 16 CHAPTER 11 ADMINISTERING IPX ROUTING Displaying IPX SAP To display IPX SAP statistics from the Administration Console top level Statistics menu enter ipx statistics sap Top Level Menu system Example ethernet interface fddi Toute summary atm server rip IPX forwarding is enabled RIP is active SAP is ac
36. metric defined 4 5 metric value DVMRP 5 5 10 3 MIB RMON 13 1 13 2 13 4 multicast routing IP about 5 1 0 on line technical services A 1 OSI Reference Model AppleTalk routing and 7 5 IP routing and 4 1 IPX routing and 6 2 P PAP 7 10 physical layer AppleTalk 7 5 pinging AppleTalk node 12 12 IP station 9 22 port See also FDDI port printer access protocol 7 10 probe RMON 13 1 13 2 PVC adding 9 9 removing 9 9 name binding protocol 7 9 named entities 7 2 NBP 7 9 NetWare defined 6 1 OSI reference model and the 6 2 protocols 6 1 to 6 3 network address 3 3 network layer and IP address 4 1 network layer AppleTalk 7 6 network numbers extended 7 2 nonextended 7 2 network supplier support A 3 nodes AppleTalk 7 2 nonextended network numbers 7 2 R rate limit IP multicast 5 6 10 4 references Comer 4 11 Perlman 4 11 routing RFCs 4 11 returning products for repair A 4 RIP active mode 9 21 broadcast address and 9 2 default mode 9 22 defined 4 6 6 10 off mode 9 21 passive mode 9 21 route configuration and 4 6 6 9 setting mode 9 21 using for dynamic routes 6 9 RIP statistics IPX RIP 11 15 RMON agents 13 3 alarms 13 6 benefits of 13 2 groups 13 3 hysteresis mechanism 13 8 LANplex implementation 13 2 management console 13 1 MIB 13 1 13 2 13 4 probe 13 1 13 2 route IP default 9 10 defining static 9 11 removing default 9 13 removing from table 9 12 status 9 10 route IPX
37. pieces of the transport system work The ping command is one frequently used way to invoke this process Creates more efficient routing ICMP Redirect Often the host route configuration specifies the minimal possible routing information needed to communicate for example the address of a single router The host relies on routers to update its routing table In the process of routing packets a router may detect a host not using the best route The router then sends the host an ICMP redirect requesting that the host use a different gateway when sending packets to that destination The next time the host sends a packet to that same destination it uses the new route Informs sources that a packet has exceeded its allocated time to exist within the network ICMP Time Exceeded 4 10 CHAPTER 4 ROUTING WITH IP TECHNOLOGY Routing with Classical IP over ATM About Logical IP Subnets LISs ATM ARP Servers LANPlex Extended Switching software supports classical IP routing over ATM ARP in an ATM network Classical IP over ATM uses Logical IP Subnets LISs to forward packets within the network environment See the LANplex 2500 Operation Guide for detailed information about the ATM protocol architecture See the LANplex 2500 Administration Console User Guide for information about how to configure ATM ports An LIS is a group of IP nodes that belong to the same subnet and which are directly connected to a single ATM network When
38. script logout interface route arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip ping statistics To display IP statistics enter the following from the top level of the Administration Console ip statistics Example IP routing is enabled RIP is active disabled ICMP router discovery is inReceives forwDatagrams inDelivers outRequests 51213 49743 3227 2285 outNoRoutes inHdrErrors inAddrErrors 273 7 0 Table 9 2 describes the IP statistics Table 9 2 IP Statistics Total number of IP datagrams received including those with errors Number of datagrams that the IP station attempted to forward Number of datagrams that the IP station delivered to local IP client Number of datagrams that local IP client protocols passed to IP for Number of datagrams that the IP station discarded because there Number of datagrams that the IP station discarded because the IP Field Description inReceives forwDatagrams inDelivers protocols outRequests transmission outNoRoutes was no route to the destination inHdrErrors header contained errors inAddrErrors Number of datagrams that the IP station discarded because of an error in the source or destination IP address 9 24 CHAPTER 9 ADMINISTERING IP ROUTING ADMINISTERING IP MULTICAST ROUTING This chapter describes how to set up your LANplexGsystem to use IP multicast routing You should have previously defined IP interfaces and routes
39. snmp statistics analyzer script logout Setting the Standard IPX RIP packets can include up to 50 route advertisements but Enhanced RIP some routers allow up to 68 Enhanced RIP mode increases the number of Mode entries in a RIP packet that the system will accept Enhanced RIP mode Enhanced RIP default Top Level Menu System ethernet fddi snmp analyzer script logout interface Toute Server bridge forwarding ip rip b ipx enhanced appletalk sap statistics allows the system greater interoperability with routers that do not explicitly follow the IPX router implementation guidelines By default enhanced RIP is disabled To enable or disable enhanced RIP mode From the Administration Console top level menu enter ipx enhanced Enter the enhanced RIP state enabled Or disabled To use the value in brackets press Return at the prompt Setting the SAP Mode 11 13 Setting the SAP Mode SAP default mode Top Level Menu system ethemet interface fddi route atm server bridge forwarding ip rip ipx enhanced appletalk sap snmp statistics analyzer script logout You can select a SAP mode that is appropriate for your network SAP can operate in any of three modes Off The system ignores all incoming SAP packets and does not generate any SAP packets of its own Passive The system processes all incoming SAP packets but it does not broadcast periodic or trigger
40. the IP interface When the LANplex Administration Console menu prompts you for Menu Top Level System etherne fddi snmp analyzer script P interface route arp atmArpS multicas udpHelp routing icmpRoy rip ping statistics logout Displaying Interfaces gt summary b detail define modify remove addAdvertisement removeAdvertisement addPVC removePVC Administering interfaces 9 3 this option the system displays a list of available VLAN indexes and the bridge ports associated with them LIS Interface When you select LIS as the interface type the Administration Console prompts you for LIS interface information The information you enter depends on whether you define permanent virtual circuits PVCs switched virtual circuits SVCs or both on the LIS interface See the LANplex 2500 Operation Guide for more information on PVCs and SVCs If you define SVCs you need to enter an ATM ARP server address This server maintains the IP to ATM address translation table You can enter the maximum number of SVCs allowed on this interface The minimum holding time determines the least amount of time an SVC connection remains open The inactivity timer determines how long the connection can remain open With no activity after the minimum holding time has expired You also need to enter the ATM port number for this interface If you define only PVCs on the interface you need to enter only the PVC numbe
41. the default VLAN serves to define The flood domain for protocols not supported by any VLAN in the system The flood domain for protocols supported by a VLAN in the system but received on nonmember ports Both cases represent exception flooding conditions that are described in the following sections Modifying the Default VLAN New switch ports can dynamically appear in the LANplex system if you insert a daughter LAN card or create an ATM LEC When a new switch port that is not part of a default VLAN appears in the system at initialization the system software adds that switch port to the first default VLAN defined in the system LANplex VLANs also allow you to modify the initial default VLAN to form two or more subsets of switch ports If you remove the default VLAN and no other VLANs are defined for the system no flooding of traffic can occur Protocol sensitive VLANs directly affect how the LANplex system performs flooding Without protocol sensitive VLANs the flooding process is to forward data to all switch ports in the system With protocol sensitive VLANS the flooding process follows this model m Asaframe is received that needs to be flooded it is decoded to determine its protocol type If a VLAN exists for that protocol in the LANplex system and the frame s source port is a member of the VLAN the frame is flooded according to the group of ports assigned to that VLAN If a VLAN exists for that protocol in the LANplex s
42. you add a node to a LIS through the Administration Console IP interface menu you define its IP address subnet mask and the address an ATM ARP server that supports it An ATM APP server maintains a table of IP addresses and their corresponding ATM addresses and circuit information To forward IP packets over an ATM interface the network node learns the ATM address for the corresponding IP address from the ATM ARP server Each ATM ARP server supports a single LIS You can associated two or more LISs with the same ATM network but each LIS operates independently of other LISs on the network Several types of network nodes can function as ATM ARP servers Any LANplex system with revision 8 1 0 or later of Extended Switching software An ATM switch A UNIX Gworkstation The following sequence describes how the ATM ARP server learns and stores information about the IP and ATM addresses of nodes in the network A node establishes a connection to the ATM ARP server The ATM ARP server sends an inverse ATM ARP request to the node requesting its IP and ATM address When the node returns this information the ATM ARP server stores or caches it in the ATM ARP server table IP Routing References 4 11 Forwarding to Nodes within an LIS Nodes can forward packets directly to other nodes in the same LIS To forward a packet within the same LIS the sending node requests a translation from the destination IP address to the corresponding ATM add
43. 00212d0f 18 1 32 158 101 112 7 47 005 80 ffe100 0000 f22a 2130 800002114d01 18 1 33 158 101 116 7 47 005 81 ffe100 0000 f21a 2130 80000112d01 18 2 20 158 101 112 14 47 005 81 ffe100 0000 f21a 2130 80000112d01 18 2 22 Removing an ATM ARP Cache Entry Menu Top Level System ethemd fddi atm bridge Dip ipx appleta snmp analyz script logout display defin display remove udpHelper flush routing icmpRouterDiscovery rip ping statistics To remove an entry from the ATM ARP cache from the top level of the Administration Console enter ip atmarpserver arp remove Enter the ATM address you want to remove The address is immediately removed from the table CHAPTER 9 ADMINISTERING IP ROUTING Flushing the ATM ARP Cache Top Level Menu system ethemd fddi atm bridge Dip ipx appleta snmp analyza script logout interface route arp efin DatmArps rem multicast arp udpHelper routing icmpRouterDiscovery rip ping statistics display display remove M flush l To remove all entries from the ATM ARP cache from the top level of the Administration Console enter ip atmarpserver arp flush The ATM ARP cache entries are immediately removed from the table Administering UDP Helper UDP Helper allows you to send User Datagram Protocol UDP packets between routed networks This protocol provides support for UDP services such as BOOTP or DHCP Dynamic H
44. 01 3 2 3 default route 255 255 255 0 1 158 101 1 2 1 Figure 4 5 Example of a Routing Table in the LANplex Routing Model Routing table information is generated and updated in either of the following ways w Statically You manually enter routes which do not change until you change them that is they will not time out a Dynamically The router uses a routing protocol such as RIP to exchange information Routes are recalculated at regular intervals Static Routes A static route is one that you manually configure in the routing table Static routes are useful in environments where no routing protocol is used or where you want to override some of the routes generated with a routing protocol Because static routes do not automatically change in response to network topology changes you should manually configure only a small number of reasonably stable routes Dynamic Routes Using RIP Automated methods of configuring routes help you keep up with a changing network environment allowing routes to be reconfigured quickly and reliably Interior Gateway Protocols IGP which operate within networks provide this automated method The LANplex system uses the Routing Information Protocol RIP one of the most widely used IGPs to configure its routing tables dynamically RIP operates in terms of active and passive devices The active devices usually routers broadcast their RIP messages to all devices in a network or subne
45. 1 network 32910 32910 You can control whether the router forwards or discards AppleTalk packets addressed to other hosts When you enable forwarding the router processes packets as usual forwarding AppleTalk packets from one subnet to another when required When you disable IP forwarding the router discards any AppleTalk packets not addressed directly to one of its defined interfaces 1 At the Administration Console s top level menu enter appletalk forwarding 2 Enter enable Or disable at the prompt 12 12 CHAPTER 12 ADMINISTERING APPLETALK ROUTING Configuring Checksum Top Level Menu System ethemet interface fddi Toute atm aarp bridge zone ip forwarding ipx checksum M appletalk ping snmp statistics analyzer script logout Pinging an Checksum is a simple method used for detecting errors in the transmission of data Checksum generation totals the bytes comprising the data and adds this sum to the end of the data packet Checksum verification allows you to verify the integrity of the data that is routed You can enable or disable checksum generation and verification states To enable or disable checksum generation verification At the Administration Console s top level menu enter appletalk checksum Enter enable Or disable at the checksum generation prompt Enter enable Or disable at the checksum verification prompt The AppleTalk Echo Protocol AEP sends a datagram an Echo Request
46. 10 2 displaying 10 4 enabling 10 5 MBONE 5 2 rate limit 5 6 10 4 INDEX 3 TTL threshold 10 3 tunnels 5 6 10 6 IP route default 9 10 9 13 defining static 9 11 removing from table 9 12 status 9 10 IP router transmission process 4 2 IP routing address classes 4 3 basic elements 4 2 enabling 9 20 ICMP 4 9 OSI reference model 4 1 references 4 11 router interface 4 4 routing table 4 5 transmission errors 4 9 IP routing over ATM 4 10 IPX forwarding statistics displaying 11 17 main menu 1 5 RIP statistics displaying 11 15 route defining a static 11 6 removing a 11 7 SAP statistics 11 16 static server 11 9 IPX routing and RIP 6 10 packet format 6 5 router interface 6 8 routing table 6 8 SAP and 6 10 server table 6 13 L LANplex bridging routing model 3 6 intranetwork router as an 3 2 ports and IP interfaces 9 6 subnetting with 3 2 learned routes flushing AppleTalk 12 6 flushing IP 9 12 flushing IPX 11 7 learned IP route status 9 10 LIS definition of 4 10 forwarding to nodes within an 4 11 LIS interfaces characteristics of 9 3 defining 9 4 M MAC Media Access Control See FDDI MAC MAC address 3 3 ARP and 9 13 bridging in switching modules and 3 6 compared to IP address 4 2 in ARP Request 4 8 located with ARP 4 7 use in IP routing 4 8 Macintosh chooser 7 2 management IP interface 9 1 management console RMON 13 1 MBONE 5 2 menu AppleTalk main 1 6 bridge 1 4 IP main 1 4 IPX main 1 5
47. 2 2 Up 4 Defining an IPX When you define an interface you define the interface s IPX address Interface cost format and the associated IPX VLAN index You must define an IPX VLAN before you define the IPX interface to associate with that VLAN To define an IPX interface premens 1 From the Administration Console top level menu enter system ethemet B interface ipx interface define fddi route display M EM cette You are prompted for the interfaces parameters To use the value in ge forwarding modify ip rip remove brackets press Return at the prompt b ipx enhanced appletalk sap ame statistics 2 Enter the IPX network address of the interface analyzer script p logout 3 Enter the cost of the interface 4 Enter the format of the interface 5 Enterthe index of the IPX VLAN associated with this interface CHAPTER 11 ADMINISTERING IPX ROUTING IPX VLANs Index 3 4 1 Example Enter IPX Address 0x45469 30 Enter Cost Enter Frame Format Ethernet II 0 802 2 1 Raw 802 3 2 SNAP 3 1 1 Ports 1 8 9 12 Select VLAN index 3 Modifying an Top Level Menu System ethemet B interface fddi atm bridge ip D ipx appletalk snmp analyzer script logout route server forwardin rip enhanced sap statistics Interface display define modify remove Removing an Top Level Menu system ethemet p interface fddi appletalk
48. 20 Europe 31 30 60 29900 option 5 44 1442 275822 Outside Europe U S and Canada 1 408 492 1790 1 408 764 7290 10 22 96 INDEX Numerics 3Com Bulletin Board Service 3ComBBS A 1 3Com sales offices A 4 3ComFacts A 3 A AARP 7 10 AARP cache administering 12 7 displaying 12 8 removing an entry from 12 9 address classes 4 3 IP to MAC translating 9 13 MAC 3 3 network 3 3 Address Resolution Protocol See ARP Administration Console menu descriptions 1 2 top level menu 1 2 ADSP 7 10 advertisement address adding 9 8 in a define interface command 9 5 removing 9 8 AEP 7 8 alarm thresholds examples of 13 7 setting 13 7 AppleTalk address resolution protocol AARP 7 10 checksum 12 12 configuring forwarding 12 11 data stream protocol ADSP 7 10 echo protocol AEP 7 8 interface displaying 12 3 main menu 1 6 name binding protocol NBP 7 9 network layer 7 6 nodes 7 2 physical layer 7 5 printer access protocol PAP 7 10 protocols about 7 1 protocols and OSI levels 7 4 routing table maintenance protocol RTMP 7 6 routing tables 7 8 session layer protocol ASP 7 10 statistics viewing 12 13 transaction protocol ATP 7 9 zone information protocol ZIP 7 9 zones 7 3 AppleTalk networks 7 2 extended 7 2 nonextended 7 2 AppleTalk node pinging an 12 12 AppleTalk routing 7 1 ARP defined 4 7 9 13 location in OSI reference model 4 1 reply 4 8 request 4 8 See also ARP cache 9 13 ARP cache 4 7 9 13
49. AP uses IPX and the medium access protocols for its transport The packet structure allows the following functions A workstation request for the name and address of the nearest server of a certain type A router request for the names and addresses of all the servers or of all the servers of a certain type on the internetwork A response to a workstation or a router request Periodic broadcasts by servers and routers Changed server information broadcasts Figure 6 5 provides an overview of the SAP packet structure Note that the packet structure is encapsulated within the data area of IPX Server Entry Structure SAP Packet Structure Service Type 2 bytes Operation 2 bytes Server Name 48 bytes Server Entry 1 64 bytes Network Address 4 bytes Node Address 6 bytes Socket Address 2 bytes Hops to Server 2 bytes Server Entry n 64 bytes n lt 7 Figure 6 5 SAP Packet Structure CHAPTER 6 ROUTING WITH IPX A SAP packet consists of the following fields Operation This field indicates the type of operation the SAP packet performs It can be set to one of the following values 1 Request 2 Response 3 Get Nearest Server Request 4 Get Nearest Server Response Server Entry Each 64 byte server entry includes information about a particular server It consists of the following fields Service Type This 2 byte field identifies the type of service the server provides Although IPX routers
50. AppleTalk VLAN associated with this interface Example Enter Start of Network Range 10000 Enter End of Network Range 10100 Enter Default Zone engineering Enter Zone Name q Appletalk VLANs Index Ports 3 1 8 4 9 12 Select VLAN index 3 You might want to remove an interface if you no longer perform routing on the ports associated with the interface To remove an AppleTalk interface At the Administration Console s top level menu enter appletalk interface remove Enter the index number s of the interface s you want to remove The interface is no longer defined on the router Administering Routes 12 5 Administering Routes Displaying the Routing Table Top Level Menu System ethernet fddi snmp analyzer script logout interface Proute display aarp flush zone forwarding checksum ping statistics Your system maintains a table of routes to other AppleTalk networks The routing table is generated automatically by the Routing Table Maintenance Protocol RTMP RTMP defines 1 the rules for exchanging information between routers so that the routers can maintain their routing tables and 2 the rules for the information contained within each routing table Each routing table entry contains the following information Network Range A range of numbers used to designate a network segment s identity Distance The distance in hops to the destination network Interface The define
51. Distance Vector Multicast Routing Protocol DVMRP establishes the multicast delivery path over a series of routing devices DVMRP is a simple distance vector routing protocol similar to the IP Routing Information Protocol RIP Multicast routers exchange distance vector updates that contain lists of destinations as well as the distance in hops to each destination They maintain this information in a routing table DVMRP is the current routing protocol used on the Internet Multicast Backbone MBONE Full support of DVMRP allows the LANplex system to fully establish the delivery path without requiring a direct connection to a multicast router The MBONE is an experimental Multicast Backbone network that exists on the Internet Users can test multicast applications and technology on the MBONE without waiting for Internet multicast standards to be set You can gain access to the MBONE through any Internet service provider The MBONE routers forward mulitcast packets over an interface or over a multicast tunnel only if the Time To Live TTL value present in the packet is larger than the tunnel s threshold See the section Multicast Tunnels on page 6 for more information about tunnels LANplex 2500 systems at revisions earlier than 8 0 support up to 16 IP multicast tunnels or routing interfaces when connected to the MBONE network LANplex 2500 systems at revision 8 0 or later can support up to 32 IP multicast tunnels or routing interfaces w
52. Extended Switching software These features include IP IP Multicast classical IP over ATM IPX and AppleTalk routing virtual LAN VLAN configuration and remote monitoring RMON Use this guide with the LANplex 2500 Administration Console User Guide when you configure your LANplex 2500 system See the LANplex 2500 Software Installation and Release Notes for information about how to install Extended Switching software on your LANplex system This guide is intended for the system or network administrator who is responsible for configuring using and managing the LANplex 2500 system It assumes a working knowledge of local area network LAN operations and a familiarity with communications protocols used on interconnected LANs If the information in the release notes shipped with your product differs from the information in this guide follow the release notes How to Use This Guide The following table shows where to find specific information If you are looking for Tum to An overview of Extended Switching features Chapter 1 Virtual LANs VLANs on the LANplex System Chapter 2 General routing and routing models in the LANplex system Chapter 3 IP routing strategies Chapter 4 IP multicast routing and its protocols Chapter 5 continued If you are looking for Tum to IPX routing and its protocols Chapter 6 AppleTalk routing network elements and protocols Chapter 7 How to administer VLANs Chapter 8 How to
53. G IP ROUTING Setting the BOOTP Hop Count Limit Top Level Menu system ethernet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route 1 arp display atmArpServer define multicast remove DudpHelper P hopCountLimit routing threshold icmpRouterDiscovery rip ping statistics Setting the BOOTP Relay Threshold Top Level Menu System ethemet ln fddi arp display atm atmArpServer define bridge multicast remove bip I udpHelper hopCountLimit 1 ipx routing M threshold appletalk snmp eee analyzer Hie 2 script Ae logout statistics You can set the maximum hop count for a packet to be forwarded through the router The range is 0 through 16 The default is 4 To set the hop count limit From the top level of the Administration Console enter ip udpHelper hopCountLimit 2 Enter the BOOTP relay hop count limit You can set the maximum time limit that a packet is forwarded through the router If you use 0 as threshold value the router ignores the seconds field If you use a non zero value the router uses that value along with the hop count value to determine whether to forward the UDP packet To set the BOOTP relay threshold From the top level of the Administration Console enter ip udpHelper threshold Enter the BOOTP relay threshold value Enabling and Disabling IP Routing Top Level Menu system ethernet fddi atm brid
54. IP ROUTING Removing a Route Top Level Menu system ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route display arp static atmArpServal remove multicast flush udpHelper default routing noDefault icmpRouterDiscovery rip ping statistics Flushing a Route Top Level Menu system ethernet fddi atm bridge bip ipx appletalk snmp analyzer script logout interface P route display arp static atmArpServa remove multicast flush udpHelper default routing noDefault icmpRouterDiscovery rip ping statistics Setting the Default Route 1 2 3 Example Enter destination IP address 158 101 4 0 255 255 0 0 255 255 255 0 158 101 2 8 Enter subnet mask Enter gateway IP address To remove a route From the top level of the Administration Console enter ip route remove Enter the destination IP address of the route Enter the subnet mask of the route The route is immediately deleted from the routing table Flushing deletes all learned routes from the routing table To flush all learned routes from the top level of the Administration Console enter ip route flush All learned routes are immediately deleted from the routing table If you define a default route the system uses it to forward packets that do not match any other routing table entry A system can learn a default route using RIP or you can configure a
55. Interface r Network 3 Figure 4 4 Router Interfaces in the LANplex System A routing table allows a router or host to determine how to send a packet toward the packet s ultimate destination The routing table contains an entry for every destination network subnet or host to which the router or host is capable of forwarding packets A router or host uses the routing table when the destination IP address of the packet it is sending is not on a network or subnet to which it is directly connected The routing table provides the IP address of a router that can forward the packet toward its destination The routing table consists of the following elements Destination IP Address the destination network subnet or host Subnet Mask the subnet mask corresponding to the destination IP address Metric a measure of the distance to the destination In the Routing Information Protocol RIP the metric is the number of hops Gateway the IP address of the next hop router the IP address of the interface through which the packet travels Interface the interface number through which a packet must travel to reach that router Figure 4 5 shows the routing table of the router in Figure 4 4 4 6 CHAPTER 4 ROUTING WITH IP TECHNOLOGY Routing Table Destination IP Address Subnet Mask Metric Gateway Interface 158 101 1 1 255 255 255 0 1 158 101 1 2 1 158 101 2 1 255 255 255 0 1 158 101 222 2 158 101 3 1 255 255 255 0 1 158 1
56. Longs inShortDdps 0 0 0 0 inCsumErrors inBcastErrors inTooFars inDiscards 0 0 0 54 outLocals 15600 Table 12 1 describes the AppleTalk DDP statistics you can view Table 12 1 AppleTalk Statistics Field Description inReceives Total number of packets received including those with errors inForwards Total number of packets forwarded including those with errors inLocals Number of DDP datagrams for which this entity was their final DDP destination inNoRoutes Number of DDP datagrams dropped because a route could not be found inNoClients Number of DDP datagrams dropped because of an unknown DDP type continued 12 14 Displaying RTMP Information Top Level Menu System ethernet interface fddi Toute summary atm aarp b rtmp bridge zone zip ip forwarding nbp ipx checksum P appletalk Ping snmp statistics analyzer script logout CHAPTER 12 ADMINISTERING APPLETALK ROUTING Table 12 1 AppleTalk Statistics continued Field Description inTooShorts Number of input DDP datagrams dropped because the received data length was less than the data length specified in the DDP header or the received data length was less than the length of the expected DDP header inTooLongs Number of input DDP datagrams dropped because they exceeded the maximum DDP datagram size inShortDdps Number of input DDP datagrams dropped because this entity was not their final destination and their type was short DDP inCsumE
57. MINISTERING IP MULTICAST ROUTING Enabling and Disabling DVMRP 10 2 Enabling and Disabling IGMP 10 2 Administering IP Multicast Interfaces 10 3 DVMRP Metric Value 10 3 Time To Live TTL Threshold 10 3 Rate Limit 10 4 Displaying Multicast Interfaces 10 4 Disabling Multicast Interfaces 10 5 Enabling Multicast Interfaces 10 5 Administering Multicast Tunnels 10 6 Displaying Multicast Tunnels 10 6 Defining a Multicast Tunnel 10 7 Removing a Multicast Tunnel 10 7 11 12 Displaying Routes 10 8 Displaying the Multicast Cache 10 9 ADMINISTERING IPX ROUTING Administering Interfaces 11 2 Displaying IPX Interfaces 11 3 Defining an IPX Interface 11 3 Modifying an Interface 11 4 Removing an Interface 11 4 Administering Routes 11 5 Displaying the Routing Table 11 6 Defining a Static Route 11 6 Removing a Route 11 7 Flushing Routes 11 7 Administering Servers 11 8 Displaying the Server Table 11 9 Defining a Static Server 11 9 Removing a Server 11 10 Flushing Servers 11 10 Setting IPX Forwarding 11 11 Setting the RIP Mode 11 11 Setting the Enhanced RIP Mode 11 12 Setting the SAP Mode 11 13 Displaying Statistics 11 14 Displaying IPX Summary Statistics 11 14 Displaying IPX RIP Statistics 11 15 Displaying IPX SAP Statistics 11 16 Displaying IPX Forwarding Statistics 11 17 ADMINISTERING APPLETALK ROUTING Administering Interfaces 12 2 Displaying AppleTalk Interfaces 12 3 Defining an Interface 12 3 Removing an Interface 12 4 Adm
58. Menu 1 From the top level of the Administration Console enter System interf ethemet Es ip multicast tunnel define an rand Hace oe bridge lp mutica tune Pome 2 Enter the index number s of the interface s with which you want to n UUDPG routeDispiay associate a multicast tunnel routing cacheDisplay appletalk icmpRouve uiscuvet y aos i 3 Enterthe IP address of the destination multicast router et statistics i The IP address of the destination multicast router must be a remote address The destination router cannot be directly connected to the same subnetworks as the local IP address 4 Enter the DVMRP metric value of the tunnel 5 Enterthe Time To Live TTL threshold of the tunnel 6 Enterthe rate limit of the tunnel Example Enter an IP interface index 1 2 Enter remote IP address 192 9 200 40 Enter tunnel DVMRP metric 1 1 Enter tunnel TTL threshold 1 Enter tunnel rate limit 0 Removing a To remove an IP multicast tunnel Multicast Tunnel Top Level Menu 1 From the top level of the Administration Console enter jr pae interface ip multicast tunnel remove fddi route d Ai a vmrp i di l bridge atmArpSt iue deme 4 Enter the index number s of the interfaces associated with the tunnel you bip P multicast tunnel l remove want to remove ipx udpHelpd routeDisplay appletal routing cacheDisplay snmp icmpRouterviscovery Example analyzer rip script ping Enter an IP
59. To use the value in H apple outing addAdvetisement brackets press Return at the prompt SNMP icmpRo removeAdvertisement analyz rip addPVvc script ping removePVC 2 Enterthe IP address of the interface logout Statistics 3 Enter the subnet mask of the network to which the interface is to be connected 4 Enter the cost value of the interface 5 Enter the type of IP interface VLAN 6 Enter the advertisement address for this interface 7 Enter the index of the VLAN associated with the interface Example Enter IP address 158 101 1 1 Enter subnet mask 255 255 0 0 255 255 255 0 Enter cost 1 Enter interfac typ vlan lis vlan Enter advertisement address es 158 101 1 255 IP VLANs Index Ports 3 1 8 4 9 12 Select VLAN index 3 j gt If you physically change the configuration of your system after defining IP interfaces the ports designated for those interfaces might no longer be valid and you might want to reconfigure your interfaces Modifying an Top Level Menu System etherne p interfacg fddi Toute arp atmAm Interface gt summary detail define multicag modify udpHeld remove routing icmpRo rip addAdvertisement removeAdvertisement addPvc ping removePvc statistics Removing an Top Level Menu system script logout statistics Interface summary detail define modif
60. Toute atmArpSENp remove multicast hopCountLimit P udpHelper threshold routing icmpRouterDiscovery rip ping statistics 9 19 Administering UDP Helper You can display the hop count and threshold configuration and list the ports with their IP forwarding addresses that are defined for your LANplex system To display UDP Helper information enter the following command string from the top level of the Administration Console ip udpHelper display Example BOOTP relay hopcount limit is 4 BOOTP relay threshold is 0 UDP port forwarding address 67 158 101 1 112 You can define port numbers and IP forwarding addresses for the UDP Helper You may have up to 32 combinations of port numbers IP forwarding addresses per router You may also have multiple IP address entries for the same ports To define port numbers and IP forwarding addresses From the top level of the Administration Console enter ip udpHelper define Enter the port numbers and IP forwarding addresses you want to define You can remove a port number or IP forwarding address defined for UDP Helper To remove a port number or IP forwarding address From the top level of the Administration Console enter ip udpHelper remove Enter the UDP port number that you want to remove Enter the IP forwarding address that you want to remove The port numbers and IP forwarding addresses you specified are immediately removed CHAPTER 9 ADMINISTERIN
61. Xerox Network System XNS a networking system developed by Xerox Corporation The NetWare operating system is based on a client server architecture where clients request certain services from servers such as file access and printer access As a network operating system environment the NetWare operating system specifies the upper five layers of the OSI reference model It provides file and printer sharing and supports various applications such as electronic mail and database access Figure 6 1 illustrates a simplified view of NetWare s better known protocols and their relationship to the OSI reference model CHAPTER 6 ROUTING WITH IPX Layers in the OSI reference model NetWare Application Appplications NetWare Service Routing Presentation n Client NetBIOS Transport Control Advertising Information Protocol Protocol SAP RIP Data Link Media Access Protocols Ethernet FDDI Physical Internet Packet Exchange IPX Figure 6 1 NetWare Protocols and the OSI Reference Model The LANplex system uses the following protocols for routing in a Netware environment Internet Packet Exchange IPX Routing Information Protocol RIP Service Advertisement Protocol SAP IPX is the primary protocol used for routing in a netware environment This datagram connectionless protocol does not require an acknowledgment for each packet sent Any packet acknowledgment or connection control must be provided by protocols
62. a LIS interface with only PVCs enter the ATM port and the PVCs associated with the interface You can enter up to 51 PVCs for each interface The maximum number on the LANplex system is 64 LIS interface example with both PVCs and SVCs Enter IP address 158 101 1 1 Enter subnet mask 255 255 0 0 255 255 255 0 Enter cost 1 Enter interface type vlan lis lis Enter advertisement address es 158 101 112 1 Enter ATM arp server address 00 0000 00 000000 0000 0000 0000 000000000000 00 47 0000 00 000000 000 00000 00cc 000000000001 ff Accept completed ATM address yes no yes Enter max SVC count 0 no max 0 0 Enter inactivity time 0 infinite 10 10000 seconds 1200 Enter min holding time 0 10000 seconds 60 Select ATM port 1 Enter PVC s VPI VCI 1 32 1 200 1 3330 9 6 CHAPTER 9 ADMINISTERING IP ROUTING Defining an IP When you define an IP VLAN interface you specify several interface VLAN Interface characteristics as well as the index of the VLAN associated with the interface p You must first define a VLAN as described in Chapter 8 Administering VLANs before you define an associated IP VLAN interface Top Level Menu To define an IP VLAN interface System I eem d inete 1 From the top level of the Administration Console enter fddi atm Toute Summary bridge 2P detail ip interface define atmArptb define TU med The Console prompts you for the interface s parameters
63. above IPX IPX defines internetwork and intranode addressing schemes IPX internetwork addressing is based on network numbers that are assigned to each interface in an IPX network IPX intranode addressing is in the form of socket numbers Since several processes are normally operating within a node socket numbers provide a type of mail slot so that each process can distinguish itself to IPX Routing Information Protocol RIP Service Advertising Protocol SAP IPX Routing in the NetWare Environment 6 3 RIP allows the exchange of routing information on a NetWare network IPX routers use RIP to dynamically create and maintain their routing tables RIP allows one router to exchange routing information with a neighboring router As a router becomes aware of any changes in the network layout it broadcasts this information to any neighboring routers IPX routers also send periodic RIP broadcast packets containing all routing information known to the router These broadcasts synchronize all routers on the network and age those networks that might become inaccessible if a router becomes disconnected from the network abnormally SAP provides routers and servers that contain SAP agents with a means of exchanging network service information Through SAP servers advertise their services and addresses Routers gather this information and share it with other routers This strategy allows routers to dynamically create and maintain a database
64. ache From the top level of the Administration Console enter ip multicast cacheDisplay You are prompted for the multicast source address Enter the multicast source subnetwork address You are prompted for the multicast group address Enter the multicast group address The DVMRP status and IGMP status appear on the screen 10 10 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING gt gt Example The following display shows the multicast cache configuration DVMRP is enabled Enter multicast source address Enter multicast group address 131 188 0 0 244 2 0 2 IGMP snooping is enabled Multicast Routing Cache Table 125 entri Origin Mcast group CTmr 202 242 133 128 26 224 2 0 1 7m 202 242 133 139 2 packets 128 84 247 24 224 2 0 1 2m 128 84 247 53 43 packets 128 84 247 156 33 packets 128 138 213 24 224 2 0 1 3m 128 138 213 1 23 packets 128 206 212 24 224 2 0 T 92s 128 206 212 69 8 packets 131 136 234 24 224 2 0 1 3m 131 136 234 103 12 packets 138 39 25 24 222 2 041 103s 138 39 25 48 46 packets 192 5 28 24 2220 32 0 L 80s 192 5 28 43 178 packets 199 94 220 24 224 2 0 1 104s 199 94 220 184 10 packets 199 104 80 24 224 2 0 1 3m 199 104 80 5 4 packets 132 197 248 21 224 2 0 1 4m 132 197 248 20 1 packets 131 188 16 224 2 0 1 3m 131 188 2 54 2492 packets 184408 149 127 16 224 270 1 2m 149 127 6 181 56 packets s Age PTmr In If 11m 36m 2h 36m 57m 4h 2h 1h 32m 6m 5h
65. ader and a data portion The network node and socket address for both the destination and source are held within the packet s IPX header Figure 6 2 shows the IPX packet format Checksum 2 bytes Packet Length 2 bytes Transport Control 1 byte Packet Type 1 byte Destination Network 4 bytes Destination Node 6 bytes Destination Socket 2 bytes Source Network 4 bytes Source Node 6 bytes Source Socket 2 bytes Upper layer Data Figure 6 2 IPX Packet Format How IPX Routing Works 6 5 The packet format consists of the following elements Checksum The IPX packet begins with a 16 bit checksum field that is set to 1s Packet Length This 16 bit field contains the length in bytes of the complete network packet This field includes both the IPX header and the data The IPX length must be at least 30 bytes Transport Control This 1 byte field indicates how many routers a packet has passed through on its way to its destination Packets are discarded when this value reaches 16 A sending node always sets this field to 0 when building an IPX packet Packet Type This 1 byte field specifies the upper layer protocol that will receive the packet s information Destination Network This 4 byte field provides the destination node s network number When a sending node sets this field to zero the destination node is assumed to be on the same local segment as the sending node Destination Node
66. affic may initially be directed to any of the routers on the LAN ICMP redirect messages will subsequently channel the IP traffic to the correct router Only certain end stations such as Solaris workstations can be configured to work with the ICMP Router Discovery protocol Refer to the documentation for your workstation to determine whether you can configure it to work with this protocol To enable ICMP Router Discovery from the top level of the Administration Console enter ip icmpRouterDiscovery Enter the ICMP Router Discovery mode enabled Or disabled This protocol is disabled by default Setting the RIP Mode You can select a RIP mode that is appropriate for your network RIP can operate in any of three modes Off The station ignores all incoming RIP packets and does not generate any RIP packets of its own Active The station processes all incoming RIP packets responds to explicit requests for routing information and broadcasts periodic and triggered RIP updates Passive The station processes all incoming RIP packets and responds to explicit requests for routing information but it does not broadcast periodic or triggered RIP updates 9 22 CHAPTER 9 ADMINISTERING IP ROUTING RIP default mode Top Level Menu system ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route arp atmArp Server multicast udpHelper routing icmpRouterDiscovery D
67. and FDDI SNAP The two FDDI encapsulation formats correspond to the Ethernet 8022 LLC and 802 3 SNAP encapsulation formats If you select either of these Ethernet encapsulation formats the corresponding FDDI encapsulation format is automatically selected for shared Ethernet and FDDI ports State The status of the IPX interface indicates whether the interface is available for communications Up or unavailable Down VLAN index The VLAN index indicates which bridge ports are associated with the IPX interface When the interface prompts you for this option it displays a list of available VLAN indexes and the ports associated with them Administering Interfaces 11 3 Displaying IPX You can display a table that shows all IPX interfaces and their parameter Interfaces settings configured for the system To display IPX interface information Top Level Mei From the Administration Console top level menu enter system mne Peer ipx interface display route atm Server De forwarding modify As shown in the following example the current configuration is bier r e er displayed It contains IPX forwarding RIP and SAP information for the letalk Sap i i amp diae system as well as IPX interface information analyzer script logout f Ogou IPX forwarding is enabled RIP is active SAP is active Index IPX address Cost Format State VLAN index 1 45469f30 T 802 2 Up 2 2 5d41a110 1 802 2 Up 1 3 6d321a22 1 80
68. atm ipxSnapTranslation modify b bridge addressThreshold remove ip agingTime ipx stpState appletalk stpPriority snmp stpMaxAge analyzer stpHelloTime script stpForwardDelay logout StpGroupAddress port packetFilter vlan Figure 1 1 Bridge Menu Hierarchy 1 4 CHAPTER 1 LANPLEX EXTENDED SWITCHING FEATURES IP Menu From the ip menu you can view information about and configure Internet Protocol IP interfaces and routes as well as IP Multicast routing You can administer the Address Resolution Protocol ARP the Routing Information Protocol RIP UDP Helper IP Forwarding and ping IP stations You can also define ATM ARP servers from the ip menu if you are running classical IP over ATM Figure 1 2 shows the ip menu To define a new IP interface for example enter ip at the top level menu interface at the ip menu and then define at the interface menu Top Level Menu ip menu interface menu system Dinterface summay ethemet b route 2 detail fddi b arp define atm b atmArpServer modify bridge multicast remove Bip 3 udpHelper addAdvertisement ipx routing removeAdvertisement appletalk icmpRouterDiscovery addPvc snmp rip removePvc analyzer ping script statistics route menu logout display static remove flush default noDefault arp menu display remove flush atmArpServer
69. cache display AARP Address 20112 125 20112 177 20112 192 20112 150 20112 1 20125 193 20125 76 20125 67 20124 41 20112 225 20112 135 20112 147 20112 132 20112 112 20112 148 20112 244 20112 21 20112 131 20124 35 20112 97 20112 4 20112 180 20112 108 20112 56 20112 110 20112 155 20112 243 20112 253 20125 104 20112 236 MAC Address 00 20 af 0b e1 7c 00 00 89 01 91 f0 00 00 89 01 91 f 3 00 00 89 01 8b 51 08 00 02 04 80 b6 08 00 07 d7 69 1f 08 00 07 66 62 9d 08 00 07 ee 10 a2 08 00 07 7c c3 d8 00 20 af 0b d8 f1 00 20 af 9e 68 62 00 00 94 41 de 79 08 00 09 7 98 c5 08 00 07 7c 20 61 08 00 07 ac 56 4b 00 20 af 0b ff 72 08 00 07 dc e5 c4 08 00 07 54 88 b1 08 00 07 57 ec 58 08 00 07 9e 09 86 08 00 07 ec 98 3d 08 00 07 7 cf de 08 00 07 4 74 7e 08 00 07 bc 10 fc 00 40 10 56 1a b5 08 00 07 6c 88 77 08 00 07 66 72 c7 08 00 20 12 75 bf 08 00 07 66 2b c2 00 80 3e 02 81 66 Interface NwWwwwrrrr rr Age secs 21 20 18 388 862 85 864 270 174 26 24 12 1098 35 8932 397 368 1925 121 110 5833 120 110 5536 4940 70 848 3841 Administering the AARP Cache 12 9 Removing an Entry To remove an AARP cache entry in the Cache Top Level Menu 1 At the Administration Console s top level menu enter system ethernet interface appletalk aarp remove fddi Toute display atm aarp remove bridge zone flush 2 Enterthe AARP address at the prompt ip for
70. ceived by SAP agents on their connected segments However SAP agents periodically broadcast their server information so that all SAP agents on the internetwork have information about all servers that are active on the internetwork Server Information Table A server information table holds information about all the servers on the internetwork SAP agents use this table to store information received in SAP broadcasts Figure 6 6 shows an example of a typical server information table Network Node Socket Hops Age 1 LPX1102 45469f33 00 00 00 00 00 01 451 2 102 1 LPX1103 45469144 00 00 00 00 00 01 451 5 65 2 LPX2001 45470001 00 00 00 00 00 01 451 4 33 Figure 6 6 Server Information Table The server information table provides the following information Interface Indicates from which interface the information was received Server Name The name of the server Server Type Indicates the type of service provided Network Address The address of the network on which the server resides Node Address The node of the server Socket Address The socket number on which the server will receive service requests Hops to Server The number of intermediate networks that must be passed through to reach the server associated with this entry Age of Server The time since the last update for that server The server information table is either statically or dynamically generated and updated CHAPTER 6 ROUTING WITH IPX
71. ch routes are configured and whether the routes are operational To display the contents of the routing table enter the following command string from the top level of the Administration Console ip route display The example shows routes for the LANplex 2500 system The display indicates the configuration of RIP The default route appears as Default Route IP routing is enabled disabled Destination 158 101 4 0 158 101 3 0 158 101 2 0 158 101 1 0 Default Route RIP Subnet mask QODLADEP ADDS 255 255 255 255 255 5 255 2555255 255 is active Metric 0 2 0 2 1 0 T 5 ICMP router discovery is Gateway 158 101 2 8 155 101 1 2 158 101 1 2 Status Static Learned RIP Direct Direct Learned RIP Before you can define static routes you must define at least one IP interface Static routes remain in the table until you remove them or the corresponding interface Static routes take precedence over dynamically learned routes to the same destination Static routes are not included in periodic RIP updates sent by the system To define a static route From the top level of the Administration Console enter ip route static You are prompted for the routes parameters To use the value in brackets press Return at the prompt Enter the destination IP address of the route Enter the subnet mask of the route Enter the gateway IP address of the route 9 12 CHAPTER 9 ADMINISTERING
72. clause at 48 C F R 52227 7013 3Com Corporation 5400 Bayfront Plaza Santa Clara California 95052 8145 For civilian agencies Restricted Rights Legend Use reproduction or disclosure is subject to restrictions set forth in subparagraph a through d of the Commercial Computer Software Restricted Rights Clause at 48 C F R 52 227 19 and the limitations set forth in 3Com s standard commercial agreement for the software Unpublished rights reserved under the copyright laws of the United States 3ComFacts Ask3Com CardFacts NetFacts and CardBoard are service marks of 3Com Corporation 3Com LANplex Transcend and NETBuilder Il are registered trademarks of 3Com Corporation CompuServe is a registered trademark of CompuServe Inc 3Com registered trademarks are registered in the United States and may or may not be registered in other countries Other brand and product names may be registered trademarks or trademarks of their respective holders Guide written edited and illustrated by Trish Crawford Lynne Gelfand Michael Jenness Dave Sullivan Patricia Johnson Michael Taillon lain Young and Bonnie Jo Collins CONTENTS ABOUT THIS GUIDE Introduction 1 How to Use This Guide 1 Conventions 2 LANplex 2500 Documentation 3 Documentation Comments 5 PARTI GETTING STARTED l LANPLEXGEXTENDED SWITCHING FEATURES About LANplex Extended Switching 1 1 Using Menus 1 2 Bridge Menu 1 3 IPMenu 14 IPXMenu 1 5 Appletalk Menu 1 6
73. d interface number State The status good suspect bad or really bad of each route You can display the routing tables for the system to determine which routes are configured and if they are operational To display the contents of the routing table From the Administration Console top level menu enter appletalk route display 12 6 CHAPTER 12 ADMINISTERING APPLETALK ROUTING The following example shows a routing table display Network Range Distance Interface State 1 1 10 good 3 4 good 0 14 6 good 5 19 7 good 61 6 good 100 100 10 good 201 300 ti good 2010 2015 2 good 0009 10009 5 good 0010 10010 7 good 0060 10060 8 good 0110 10113 5 good 0116 10117 5 good 0118 10118 6 good 0119 10119 4 good 0120 10120 y good 0122 10122 9 good 0310 10329 10 good 0410 10410 8 good 1010 11019 9 good Flushing all Routes Flushing deletes all dynamically learned routes from the routing table Top Level Menu system To flush all learned routes ethernet interface fddi B route display Y am aap flush 1 At the Administration Console s top level menu enter bridge zone ip forwarding appletalk route flush ipx checksum M appletalk ping snmp statistics analyzer script logout Administering the AARP Cache 12 7 Administering the AARP Cache AARP allows hardware addresses to be mapped to an AppleTalk protocol address AppleTalk uses dynamically assigned 24 bit addresses unlike the statica
74. ddress Resolution Protocol ARP translates the next hop IP address into a physical MAC address The router sends the packet over the network to the next hop These routing elements are described in more detail in the following section Elements of IP Routing IP Addresses IP routers use the following elements to transmit packets in a subnetworking environment IP addresses Router interfaces Routing tables Address Resolution Protocol ARP IP addresses are 32 bit addresses composed of a network part the address of the network on which the host is located and a host part the address of the host on that network See Figure 4 2 IP addresses differ from Ethernet and FDDI MAC addresses which are unique hardware configured 48 bit addresses IP Address 32 bits network host The boundary between network and host parts depends on the class of IP Figure 4 2 IP Address Network Part and Host Part A central agency assigns the network part of the IP address and the network administrator assigns the host part All devices connected to the same network share the same IP address prefix the network part of the address Elements of IP Routing 4 3 Address Classes The boundary of the network part and the host part depends on the class that the central agency assigns to your network The primary classes of IP addresses are Class A Class B and Class C Class A addresses have 8 bits for the network part
75. default route statically If a system s routing table does not contain a default route either statically configured or learned using RIP then it cannot forward a packet that does not match any other routing table entry If this occurs then the module drops the packet and sends an ICMP destination unreachable message to the host that sent the packet Top Level Menu System a interface diai i isplay atm d ites static bridge atmArpServe remove hip multicast flush ipx udpHelper default appletalk ro uting noDefault snmp icmpRouterDiscovery analyzer rip script ping logout statistics Removing the Default Route Top Level Menu Administering the ARP Cache 9 13 To statically configure the default route 1 From the top level of the Administration Console enter ip route default 2 Enterthe gateway IP address of the route The default route is immediately added to the routing table To remove a default route enter the following command string from the top level of the Administration Console ip route noDefault system The default route is immediately removed from the routing table E ub interface am Proute display bridge amp static bip multicast remove ipx atmArpServi Med udpHelper default FU routing noDefault analyzer icmpRouter IScovery script ni logout statistics Administering The LANplex system uses the Address Resolution Protocol ARP to find th
76. e multicast tunnel IP disable am igmp display multicast l interfad enable udpHelpe tunnel disable 2 routing routeDisplay icmpRouty cacheDisplay rip ping statistics 3 4 Administering IP Multicast Interfaces 10 5 To disable multicast routing on an interface From the top level of the Administration Console enter ip multicast interface disable Enter the index number of the interface you want to disable The interface is disabled Multicast routing is enabled on all existing IP interfaces when you have not specifically disabled it You can use this option to change the characteristics of an existing interface or to enable an interface that you had previously disabled To enable a multicast interface or modify the multicast characteristics of an existing IP interface From the top level of the Administration console enter ip multicast interface enable Enter the index number s of the interface s you want to enable Enter the DVMRP metric value of the chosen interface s Enter the Time To Live TTL threshold of the chosen interface s Enter the rate limit of the chosen interface s Example Enter an IP interface index 1 2 Enter Interface DVMRP metric 1 1 Enter Interface TTL threshold 1 Enter interface rate limit in KBits sec 0 10 6 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING Administering A multicast tunnel allows multicast packets to cross several unicast router
77. e the ARP Cache MAC addresses corresponding to the IP addresses of hosts and routers on the same subnets An ARP cache is a table of known IP addresses and their corresponding MAC addresses 9 14 CHAPTER 9 ADMINISTERING IP ROUTING Displaying the ARP You can display the contents of the ARP cache for your system Cache void dii To display the contents of the ARP cache enter the following command sum string from the top level of the Administration Console ethernet interface g fddi route ip arp display atm bap M display bridge atmArpSery remove hip multicast flush 1px udpHelper appletalk routing Example display of the contents of the ARP cache snmp icmpRouterDiscovery analyzer rip script ping P routing is enabled m is active logout statistic s CMP router discovery is disabled P address F Hardware address Circuit 584 101 2 2 00 40 0b 40 64 e6 58 d 2 7 08 00 20 76 a2 f2 58 101 6s 2 00 80 3e 02 68 00 58 101 2 14 08 00 09 4e 24 20 58 101 6 16 2 00 80 3e 02 8e 6a 58 101 6 LT 2 00 80 3e 02 8e 7 5e 6 18 2 00 80 3e 02 8e 94 58 101 2 22 08 00 20 04 d1 5e 58 101 6 19 2 00 80 3e 02 8e 2b 58 101 2 28 08 00 09 8c de 3a 58 101 2 29 08 00 09 82 d8 1b 5984101 6 27 A 00 80 3e 1d 75 00 Removing an ARP Cache Entry Top Level Menu System ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface
78. e host or router first looks in its ARP cache a table of IP addresses with their cor responding MAC addresses Each device participating in IP routing maintains an ARP cache See Figure 4 6 ARP Cache IP Address MAC Address 158 101 1 1 00308e3d0042 158 101 2 1 0080232b00ab Figure 4 6 Example of an ARP Cache If the IP address does not have a corresponding MAC address listed the host or router broadcasts an ARP request packet to all the devices on the network The ARP request contains information about the hardware and 4 8 CHAPTER 4 ROUTING WITH IP TECHNOLOGY protocol The two key elements of the ARP request are the target and source addresses for both the hardware MAC addresses and the protocol IP addresses See Figure 4 7 ARP Request 00802322b00ad Source hardware address 158 101 2 1 Source protocol address Target hardware address 158 101 2 15 Target protocol address Figure 4 7 Example of an ARP Request Packet When the devices on the network receive this packet they examine it and if their address is not the target protocol address they discard the packet When a device receives the packet and confirms that its IP address matches the target protocol address this device places its MAC address in the target hardware address field and sends the packet back to the source hardware address When the originating host or router receives the ARP reply it places the new MAC addre
79. e top level of the Administration Console enter ip multicast igmp The interface prompts you to enable or disable IGMP query mode and IGMP snooping mode Example Enter igmp snooping mode enabled disabled enabled enabled Enter igmp query mode enabled disabled enabled enabled Administering IP Multicast Interfaces The IP multicast interface selections allow you to enable and disable multicast characteristics on previously defined IP interfaces A multicast interface has three characteristics explained next DVMRP Metric Value The DVMRP metric value determines the cost of a multicast interface The higher the cost the less likely it is that the packets will be routed over the interface The default value is 1 Time To Live TTL Threshold The TTL threshold determines whether the interface will forward multicast packets to other switches and routers in the subnetWORK If the interface TTL is greater than the packet TTL then the interface does not forward the packet The default value is 1 which means that the interface will forward all packets 10 4 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING Rate Limit The rate limit determines how fast multicast traffic can travel over the interface in kilobytes per second Multicast traffic may not exceed this rate limit or the LANplex system will drop packets in order to maintain the set rate The default is set to 0 which implies no rate limit In all other instanc
80. each interface the route provides the status information in Table 9 1 Table 9 1 Interface Status Information Status Description Direct Route goes to a directly connected network Static Route was statically configured Learned Route was learned using indicated protocol Timing out Route was learned but is partially timed out Timed out Route has timed out and is no longer valid In addition to the routes to specific destinations the routing table can contain an additional entry called the default route The system uses the default route to forward packets that do not match any other routing table entry You might want to use a default route in place of routes to numerous destinations that all have the same gateway IP address Displaying the Routing Table Top Level Menu System ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route P display am static atmArpServg emove multicast flush udpHelper default routing noDefault icmpRouterDiscovery rip ping statistics Defining a Static Route Top Level Menu System ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface M route display arp M static atmArpServ4_ remove multicast flush udpHelper default routing noDefault icmpRouterDiscovery rip ping statistics Administering Routes 9 11 You can display a switching module s routing table to determine whi
81. ed SAP updates or respond to SAP requests Active The system processes all incoming SAP packets responds to explicit requests for routing information and broadcasts periodic and triggered SAP updates By default SAP is off To set the SAP operating mode From the Administration Console top level menu enter ipx sap Enter the SAP mode off passive Of active To use the value in brackets press Return at the prompt 11 14 CHAPTER 11 ADMINISTERING IPX ROUTING Displaying Statistics Displaying IPX Summary Statistics Top Level Menu The Administration Console allows you to display four types of IPX related statistics IPX summary statistics IPX RIP statistics IPX SAP statistics IPX forwarding statistics To display IPX summary statistics from the Administration Console top level menu enter ipx statistics summary System ethernet interface fddi Toute b summary atm server rip Example bridge forwarding sap i rip i l l Se enhanced forwarding IPX forwarding is enabled RIP is active SAP is active appletalk Sap ae pert Received Transmitted Dropped Msg Pool Empty script 1170878 565099 0 0 logout Table 11 1 describes the IPX summary statistics Table 11 1 IPX Summary Statistics Field Description Received Number of IPX packets received Transmitted Number of IPX packets transmitted Dropped Number of IPX packets dropped Msg Pool Empty Number of IPX RIP or IPX SAP
82. elephone Number Australia up to 14400 bps 61 2 9955 2073 France up to 14400 bps 33 1 69 86 69 54 Germany up to 9600 bps 49 89 627 32 188 or 49 89 627 32 189 Hong Kong up to 14400 bps 852 2537 5608 Italy fee required up to 14400 bps 39 2 273 00680 Japan up to 14400 bps 81 3 3345 7266 Singapore up to 14400 bps 65 534 5693 Taiwan up to 14400 bps 886 2 377 5840 U K up to 28800 bps 44 1442 278278 US up to 28800 bps 1 408 980 8204 A 2 APPENDIX A TECHNICAL SUPPORT Access by Digital Modem ISDN users can dial in to 3ComBBS using a digital modem for fast access up to 56 Kbps To access 3ComBBS using ISDN dial the following number 408 654 2703 World Wide Web Site Access the latest networking information on 3Com s World Wide Web site by entering our URL into your Internet browser http www 3Com com This service features news and information about 3Com products customer service and support 3Coms latest news releases selected articles from 3TECH journal 3Com s award winning technical journal and more 3ComForum on 3ComForum is a CompuServe service containing patches software drivers CompuServe and technical articles about all 3Com products as well as a messaging section for peer support To use 3ComForum you need a CompuServe account To use 3ComForum 1 Log on to CompuServe 2 Entergo threecom 3 Press Return to see the 3ComForum Main menu 3ComFacts Automated Fax S
83. er one or more switch ports This simple implementation of VLANs requires little configuration All frames received on a port are grouped together For example all frames received on a port that is part of a port group are kept within that port group regardless of 2 2 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM the data contained in the frames Port groups are useful when traffic patterns are known to be directly associated with particular ports They can benefit the user by restricting traffic based on a set of simple rules MAC Address Group VLANS VLANs allow a switch to make filtering decisions based on grouping MAC addresses together These MAC address groups can be configured so that stations in the group can only communicate with each other or with specific network resources This solution is good for security It allows the VLAN association to move with the station However MAC address grouped VLANs may require complex configuration in comparison to other types of VLANs i Port group and MAC address group VLANs are supported using the packet filtering capabilities in the LANplex system For information on port group and MAC address group filtering refer to your LANplex Operation Guide and LANplex Administration Console User Guide Application Oriented VLANS Using the LANplex filtering capability application specific traffic such as telnet traffic or FTP traffic can be filtered based on higher layer information You create this appl
84. ervice Support from Your Network Supplier A 3 3Com Corporations interactive fax service 3ComFacts provides data sheets technical articles diagrams and troubleshooting instructions on 3Com products 24 hours a day seven days a week Call 3ComFacts using your Touch ToneGtelephone at one of these international access numbers Country Telephone Number Hong Kong 852 2537 5610 U K 44 1442 278279 US 1 408 727 7021 Local access numbers are available within the following countries Country Telephone Number Country Telephone Number Australia 800 123853 Netherlands 06 0228049 Belgium 0800 71279 Norway 800 11062 Denmark 800 17319 Portugal 0505 442607 Finland 98 001 4444 Russia Moscow only 9560815 France 05 90 81 58 Spain 900 964445 Germany 0130 8180 63 Sweden 020 792954 Italy 1678 99085 UK 0800 626403 Support from Your Network Supplier If additional assistance is required contact your network supplier Many suppliers are authorized 3Com service partners who are qualified to provide a variety of services including network planning installation hardware maintenance application training and support services When you contact your network supplier for assistance have the following information ready Diagnostic error messages A list of system hardware and software including revision levels Details about recent configuration changes if applicable If you are unable to contact your network supplie
85. es the lower the rate limit the more limited the traffic over the interface Displaying To display a multicast interface Multicast Interfaces Top Level Menu 1 From the top level of the Administration Console enter system interface ethemel route dvmrp fddi am igmp display atm atmArpSelb interface enable bridge l multicast tunnel disable 2 Enter the index numbers of the interfaces you want to display dip udpHelpe routeDisplay ipx routing cacheDisplay appletall icmpRouteruiscovery snmp rip analyzer pi i wit saisis Example multicast interface configuration logout ip multicast interface display Index Local Address Metric Threshold RateLimit State 1 158 101 112 32 1 1 0 queries pkts in 0 pkts out 0 port 3 peers 158 101 112 204 3 6 0x8e 158 101 112 202 3 6 0x8f port 3 groups 224 2 F2 e255 3 6 0x8e 224 2 143 24 port 4 groups 224 2 143 24 224 2 127 225 Disabling Multicast Interfaces Top Level Menu System fddi atm bridge b ip ipx appletal snmp analyzer script logout ethemet interface route arp mr udpHelpey routeDisplay routing cacheDisplay icmpRouterviscovery rip ping statistics Enabling Multicast Interfaces Top Level Menu system ethemel fddi atm bridge b ip ipx appletal snmp analyzer script logout interface Toute dvmrp I dvmrp igmp display 2 atmArpSelp interfa enabl
86. estgroup 4 northgroup Layer 3 158 101 111 16 none 158 101 112 14 Example of a detailed display for the VLANs 255 255 255 0 255 255 255 0 Select menu option bridge vlan detail Index Protocol Identifier Ports I default 0 1 17 2 IP 2 1 5 7 3 IPX 3 8 10 4 IP 4 7 12 15 Index Name Layer 3 T none 2 eastgroup l1587 101 111 16 255 255 255 0 3 westgroup none 4 northgroup 158 101 112 14 255 255 255 0 index inPackets inBytes outPackets outBytes 1 342 3676 322 2987 2 125 7654 118 6897 3 345 7554 289 7431 4 876 8651 765 7969 Table 8 1 describes these statistics Table8 1 Fields for VLAN Information Field Description Index A system assigned index used for identifying a particular VLAN Protocol The protocol suite of the VLAN Identifier A unique user defined 4 byte integer for use by global management operations Ports The numbers of the ports assigned to the VLAN Name A 16 byte character string intended to identify the members of the VLAN Layer 3 Optional parameters consisting of IP subnet and mask used to set up flood domains for overlapping IP VLAN subnets continued Defining VLAN Information 8 3 Table8 1 Fields for VLAN Information continued Field Description inPackets Number of flooded broadcast and multicast packets that were received on the VLAN inBytes Number of flooded broadcast and multicast bytes that were received on the VLAN outPackets Number of flooded broadcast and multicast packets t
87. estination MAC address and forwards the packet to that segment Router Routing Layer 1 2 3 Router Interfaces 6 i Bridge 2 iz Esq l d L Bridging Layer l NE d H E Pg od o Kk a i bai i i Subnets E ili 2 a y pay Transmitting Host Destination Host Figure 3 6 Bridging in the LANplex Bridging and Routing Model Bridging and Routing Models 3 7 In the LANplex bridging and routing model a packet is routed as follows see Figure 3 7 The packet enters the LANplex system The packet s destination address is examined by the bridging layer The destination address corresponds to the address of one of the system ports configured for routing as opposed to a learned end station address The packet is passed to the router interface associated with the port on which the packet was received The routing layer a Selects a destination interface based on the destination network address b Determines the MAC address of the next hop either the destination host or another gateway c Passes the packet back to the bridging layer The bridging layer then selects a segment port based on the destination MAC address and forwards the packet to that segment 4 Ro
88. find a resource on the network For example you may want to gain access to a printer on the network Instead of searching the whole network when you want to print a file to a certain printer the router searches for it within a particular zone You gain access to the printer more 7 4 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT Seed Routers quickly within the zone because the zone includes fewer devices than the entire internet does A seed router initializes the internet with AppleTalk configuration information including network numbers and zone names The seed router broadcasts this information so that nonseed routers can learn it You can designate a seed router through the Administration Console A nonseed router listens for a seed router and then takes the configuration information from the first seed router it detects After a nonseed router obtains the configuration information it can participate in the network as if it were a seed router as well AppleTalk Protocols AppleTalk protocols work together to ensure the seamless flow of information throughout the AppleTalk internet Figure 7 2 shows a simplified view of AppleTalk protocols and their relationship to the OSI reference model Together these protocols provide the following services Physical Connectivity End to End Services Reliable Data Delivery OSI Reference Model Application Figure 7 2 AppleTalk Protocols and the OSI Reference Model AppleTalk Pr
89. for source ports 1 10 IP port 12 VLAN 1 IP data received on source port 12 does not match any defined source port for IP VLAN so the Default VLAN is used The LANplex system also gives you the ability to assign network layer information to IP VLANs This capability allows network administrators to manage their VLANs by subnet Flooding decisions are made by first matching the incoming frame using the protocol IP and then matching it with layer 3 subnet information If received data is IP but does not match any defined IP subnet VLAN it is flooded within all IP VLANs using the relevant switch port For example two IP VLANs can be configured for ports 1 10 as follows IP VLAN 1 Subnet 158 101 112 0 ports 1 10 IP VLAN 2 Subnet 158 101 113 0 ports 1 10 This example shows how flooding decisions are made using overlapping IP VLANs assuming a 12 port switch Network Index VLAN Address Mask Ports 1 Default none 1 12 2 IP 158 103 122 0 1 6 255 255 255 0 3 IP 158 103 123 0 6 12 255 255 255 0 2 8 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM Routing Between VLANs Data received on Is flooded on Because IP subnet VLAN 2 IP network layer matches layer 3 address for 158 103 1222 VLAN 2 on port 6 IP subnet VLAN 3 IP network layer matches layer 3 address for 158 103 1232 VLAN 3 on port 6 IP subnet VLAN 2 and IP network layer does not match any layer 3 158 103 1242 VLAN 3 address for IP VLANS on port 6
90. ge b ip ipx appletalk snmp analyzer script logout interface route arp atmArpserver multicast udpHelper B routing rip ping statistics icmpRouterDiscovery 2 You can control whether the system forwards or discards IP packets addressed to other hosts When you enable IP routing the switching module acts as a normal IP router forwarding IP packets from one subnet to another when required When you disable IP routing the system discards any IP packets not addressed directly to one of its defined IP interfaces By default IP routing is disabled on the system To enable or disable IP routing From the top level of the Administration Console enter ip routing Enter the IP routing state enable Or disable 9 21 Enabling and Disabling ICMP Router Discovery Enabling and Disabling ICMP Router Discovery Top Level Menu System ethernet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route arp atmArpserver multicast udpHelper routing icmpRouterDiscovery rip ping statistics The Internet Control Message Protocol ICMP Router Discovery protocol RFC 1256 allows an appropriately configured end station to locate one or more routers on the LAN to which it is attached The end station then automatically installs a default route to each of the routers running ICMP Router Discovery You do not need to manually configure a default route While IP tr
91. hange are when a server is disconnected or becomes accessible through a better route To relay this changed information to the rest of the internetwork the SAP agent immediately sends a broadcast to all of its directly connected segments except the segment from which the information was received This broadcast packet contains information regarding the server change The change information is also reflected in all future periodic broadcasts SAP Aging Router SAP agents implement an aging mechanism to handle conditions that cause a SAP agent to go down suddenly without sending a DOWN broadcast Examples of such changes are a hardware failure power interruptions and power surges A SAP agent maintains a timer for each entry in its server information tables that keeps track of how much time has The Elements of IPX Routing 6 15 elapsed since information was received concerning a particular table entry Since this information is either new or changed the SAP agent that receives this information immediately passes it on and the change is quickly learned throughout the internetwork SAP Request Handling When a SAP agent receives a general request it sends the sending source a SAP response packet containing information about all servers of any type known to the receiving SAP agent This response includes the same information sent out in a periodic broadcast When the request is specific the SAP agent sends a SAP response directly to the reques
92. he network It causes the destination node to return or echo the datagram to the sending node This protocol can determine whether a node is accessible before any sessions are started and it can enable users to estimate the round trip delay time between two nodes AppleTalk Protocols 7 9 AppleTalk Transaction Protocol ATP This protocol along with the AppleTalk Data Stream Protocol ADSP ensures that DDP packets are delivered to a destination without any losses or corruption Name Binding Protocol NBP This protocol translates alphanumeric entity names to AppleTalk addresses It maintains a table that references the addresses of nodes and named entities that reside in that node Because each node maintains its own list of named entities the names directory within an AppleTalk network is not centralized It is a distributed database of all nodes on the internet The Session Layer Protocols An AppleTalk internet has four session layer protocols Zone Information Protocol ZIP AppleTalk Data Stream Protocol ADSP AppleTalk Session Layer Protocol ASP Printer Access Protocol PAP The Zone Information Protocol ZIP ZIP works with RTMP to maintain a table that maps network numbers to network zones for the entire AppleTalk internet Network zones are the logical groupings of AppleTalk networks As we have seen it the table created by ZIP is called the Zone Information Table ZIT The Administration Console allows you to vie
93. hen connected to the MBONE Multicast Routing Algorithms 5 3 Multicast Routing Algorithms Flooding Spanning Trees The LANplex system uses three algorithms that support multicast routing Flooding Spanning Trees Reverse Path Forwarding Several types of flooding algorithms exist but they all share the same general principles a node in the network receives a packet that was sent to a multicast destination The node determines whether the packet is an original that it has not seen before or a duplicate of a packet that it has seen before If the packet is an original the node forwards the packet on all interfaces except the incoming interface If the packet is a duplicate the node discards it The flooding algorithm is useful in situations where the most important requirement for the network is robustness It does not depend on any kind of routing tables Destinations will receive packets as long as at least one path to them exists and no errors occur during transmission The Spanning Tree algorithm detects loops and logically blocks redundant paths in the network The paths form a loopless graph or tree spanning all the nodes in the network A port in the blocking state does not forward or receive data packets After the algorithm eliminates extra paths the network configuration stabilizes When one or more of the paths in the stable topology fail the protocol automatically recognizes the changed configuration and ac
94. his occurrence You can assign alarms with Transcend Enterprise Manager or any other SNMP network management application to monitor any counter gauge time tick or integer Consult the documentation for your management application for details on setting up alarms Setting Alarm Thresholds Example of an Alarm Threshold Alarms 13 7 Thresholds determine when an alarm reports that a counter has exceeded a certain value You can set alarm thresholds through the network manually and choose any value for them that is appropriate for your application The network management software monitors the counters and thresholds continually during normal operations to provide data for later calibration Figure 13 3 shows a counter with thresholds set manually Counter A y er sp set high threshold user specified esce set low m user specified Time Figure 13 3 Manually Set Thresholds You can associate an alarm with the high threshold the low threshold or both The actions taken because of an alarm depend on the network management application 13 8 CHAPTER 13 REMOTE MONITORING RMON TECHNOLOGY RMON Hysteresis The RMON hysteresis mechanism provides a way to prevent small Mechanism fluctuations in counter values from causing alarms This mechanism generates an alarm only under the following conditions The counter value exceeds the high threshold after previously exceeding the low threshold An alarm does not occu
95. ication oriented VLAN by configuring packet filters that specify data and offsets of the data within received packets For example to use a filter on a particular port for all telnet traffic create a a filter that discards all TCP traffic received on the telnet port IP multicast routing and autocast VLANs are additional VLAN features in the LANplex that can be used to group IP multicast traffic for specific applications For more information on how the LANplex system manages IP Multicast traffic see Chapter 8 Protocol Sensitive VLANS When the LANplex system receives data that has a broadcast multicast or unknown destination address it forwards the data to all ports This process is referred to as bridge flooding Protocol sensitive VLANs group one or more switch ports together for a specified network layer 3 protocol such as IP or AppleTalk These VLANs make flooding decisions based on the network layer protocol of the frame In addition for IP VLANs you can also make flooding decisions based on P LANplex Protocol Sensitive VLAN Configuration About VLANs 2 3 layer 3 subnet address information Protocol sensitive VLANs allow the restriction of flood traffic for both routable and nonroutable protocols They have a relatively simple configuration comprising one or more protocols and groups of switch ports These protocol sensitive VLANs operate independent of each other Additionally the same switch port can belong to multip
96. ides a way to monitor and analyze a local area network LAN from a remote location RMON is defined by the Internet Engineering Task Force IETF in documents RFC 1271 and RFC 1757 A typical RMON implementation has two components The Probe Connects to a LAN segment examines all the LAN traffic on that segment and keeps a summary of statistics including historical data in its local memory The Management Console Communicates with the probe and collects the summarized data from it The console does not need to reside on the same network as the probe and can manage the probe through SNMP The RMON specification consists almost entirely of the definition of the MIB The RMON MIB contains standard MIB variables defined to collect comprehensive network statistics that alert a network administrator to significant network events If the embedded RMON agent operates full time it will collect data on the correct port at the time the relevant network event occurs This chapter includes the following information about RMON Benefits of RMON LANplex RMON implementation The Management Information Base MIB Alarms 13 2 CHAPTER 13 REMOTE MONITORING RMON TECHNOLOGY Benefits of RMON Traditional network management applications poll network devices such as switches bridges and routers at regular intervals from a network management console The console gathers statistics identifies trends and can highlight network events The cons
97. inistering Routes 12 5 Displaying the Routing Table 12 5 Flushing all Routes 12 6 Administering the AARP Cache 12 7 Displaying the AARP Cache 12 8 Removing an Entry in the Cache 12 9 Flushing All Cache Entries 12 9 Displaying the ZoneTable 12 10 PART V 13 PART VI A Configuring Forwarding 12 11 Configuring Checksum 12 12 Pinging an AppleTalk Node 12 12 Viewing Appletalk Statistics 12 13 Displaying DDP Statistics 12 13 Displaying RTMP Information 12 14 Displaying ZIP Information 12 15 Displaying NBP Information 12 17 REMOTE MONITORING RMON AND THE LANPLEX SYSTEM REMOTE MONITORING RMON TECHNOLOGY What IsRMON 13 1 Benefits of RMON 13 2 LANplex RMON Implementation 13 2 3Com Transcend RMON Agents 13 3 Management Information Base MIB 13 4 MIB Objects 13 4 Alarms 13 6 Setting Alarm Thresholds 13 7 Example of an Alarm Threshold 13 7 RMON Hysteresis Mechanism 13 8 APPENDIX TECHNICAL SUPPORT On line Technical Services A 1 3Com Bulletin Board Service A 1 Access by Analog Modem A 1 Access by Digital Modem A 2 World Wide Web Site A 2 3ComForum on CompuServe A 2 3ComFacts Automated Fax Service A 3 Support from Your Network Supplier A 3 Support from 3Com A 4 Returning Products for Repair A 4 INDEX ABOUT THIS GUIDE Introduction gt Audience description gt The LANplex 2500 Extended Switching User Guide provides information about the features included with the LANplex
98. interface index 1 2 logout statistics The tunnel is removed 10 8 CHAPTER 10 ADMINISTERING IP MULTICAST ROUTING Displaying Routes To display all available routes in the IP multicast routing table Top Level Menu 1 From top level of the Administration Console enter ip multicast routeDisplay i The DVMRP status and IGMP status appear on the screen atm igmp bridge interface Dip M multicast tunnel ipx udpHelpd routeDisplay appletal routing cacheDisplay snmp icmpRouterDiscovery 7 analyzer rip The following display shows all available multicast routes script ping logout statistics Multicast Routing Table 2598 entries Origin Subnet From Gateway Metric Tmr In If Out Ifs 157 88 29 1732 T37 39 229 98 18 25 T1 EL 137 392 2547 32 1373393229598 5 25 Tl I1 131 215 125 236 32 137 39 229 98 14 25 T1 I1 130 118 106 254 32 137 39 229 98 10 25 T1 IRAk 129 127 118 12 32 137 39 229 98 10 25 Tl I1 129 127 110 12 32 137 39 229 98 10 25 T1 fal 129 12 110 011432 134 39 229 98 13 25 Tl I1 129 127 110 5 32 1377999152294 98 10 25 Tl I1 129 95 63 12 32 137 39 229 98 13 25 Tl LL 129 95 63 11 32 1373395229398 31 25 Tl Il 129 95 63 9 32 137 39 229 98 13 25 Tl I1 129 95 63 8 32 137 439 229 98 13 25 Ti Ll 129 95 63 6 32 197 39 229 98 13 25 Tl IL 12 9 956342732 13475599229 98 13 25 Ti TL 129 95 48 4 32 137 29 229 99 13 25 Tl I1 129 95 48 3 32 137 39 229 98 13 25 T1 pi 129 95 48 2 32 137539 229 99 13
99. ion on how AppleTalk routing works see Chapter 7 Routing with AppleTalk You can display and configure the following AppleTalk interfaces Routes AARP cache Zones AppleTalk forwarding Checksum generation and verification AppleTalk statistics 12 2 CHAPTER 12 ADMINISTERING APPLETALK ROUTING Administering Interfaces gt gt An AppleTalk interface defines the relationship between an AppleTalk Virtual LAN VLAN and the AppleTalk network Every AppleTalk interface has one AppleTalk VLAN associated with it Each switching module has one AppleTalk interface defined for each subnet directly connected to it You must first define a VLAN as described in Chapter 8 before you define an associated AppleTalk interface You can configure a maximum of 32 interfaces per router An AppleTalk interface has several elements associated with it Seed Interface You can configure the interface to be a seed interface or non seed interface Seed interfaces initialize the network with the configuration information the administrator enters These include network range address zone name and ports Non seed interfaces wait and listen for a seed interface and then take this configuration initialization information from the first seed interface they detect After the non seed interface obtains a network configuration it begins to participate in the routing of the network Network Range A range of numbers used to designate a netwo
100. ion on the LANplex system About IP Multicast Routing IP multicast routing is an extension of the Internet Protocol Multicast routing allows a router or switch to send packets to a specific group of hosts without using broadcasts or multiple unicast transmissions This group can include members that reside on the local LAN members that reside on different sites within a private network or members that are scattered throughout the Internet Mulitcast routing achieves this functionality without loops or excess transmissions IP Multicast support within the LANplex system has two main components Internet Group Management Protocol IGMP Distance Vector Multicast Routing Protocol DVMRP This chapter describes these two protocols as well as the algorithms that the LANplex system uses for multicast routing IGMP The LANplex system is capable of dynamic multicast filtering based on the Internet Group Management Protocol IGMP This protocol ensures that multicast packets are flooded only to the appropriate ports within a routing interface IGMP tracks end station group membership within a multicast group Membership in a group is dynamic and hosts are allowed to be a member of more than one group at a time Broadcast domains are maintained by avoiding propagation of multicast broadcasts to the entire subnet by confining them within the group IGMP snooping 5 2 CHAPTER 5 ROUTING WITH IP MULTICAST The MBONE The
101. keting L PB pP DUO LE Figure 3 2 Subnetted Architecture with LANplex Switching Hubs What Is Routing 3 3 Integrating The LANplex system integrates bridging and routing Multiple switch Bridging and Routing P ports can be assigned to each subnet See Figure 3 3 Traffic between ports assigned to the same subnet is switched transparently using transparent bridging or Express switching described in the LANplex amp 2500 Operation Guide Traffic traveling to different subnets is routed using one of the supported routing protocols In the following descriptions of bridging and routing on the LANplex system the term MAC address refers to a physical hardware address Theterm network address refers to a logical address that applies to a specific protocol Subnet 4 LANplex 2500 FDDI ports Ethernet ports Subnet 3 T EEA ET ET T TTT A
102. l of the Administration Console enter ip interface removeAdvertisement Enter the index interface number and the advertisement address you want to remove Adding a Permanent Virtual Circuit PVC Top Level Menu atm route summary bridge aP detail bip atmArp define multica modify appleta udpHel remove snmp routing addAdvertisement analyze icmpRo removeAdvertisement script P haddPvc ping removePvc logout iere Removing a Permanent Virtual Circuit PVC Top Level Menu System th Aare M interfac atm route summary bridge am detail bip multical define atmArp modify udpHel remove routing addAdvertisement icmpRo removeAdvertisement i addPvc ipx appleta snmp analyzel 2 3 Administering Routes 9 9 This command adds a PVC to an LIS interface To add a PVC From the top level of the Administration Console enter ip interface addPvc Enter the index interface number that you want to associate with the PVC Enter the Virtual Path Interface VPI and the Virtual Circuit Interface VCI pairs in this format ve1 vcz Separate additional entries with a comma Example Select interface index 1 1 Enter VPI VCI 2 20 This command removes one or more PVCs associated with an LIS interface To remove a PVC from the top level of the Administration Console enter ip interface removePVC Enter the index number of the interface you want to remove and the
103. laying Statistics To display IPX Forwarding statistics from the Administration Console top level menu enter Forwarded 0 Addr Errors 13758 NetBIOS Max Hops 0 Table 11 4 describes the IPX forwarding statistics 11 18 CHAPTER 11 ADMINISTERING IPX ROUTING Table 11 4 IPX Forwarding Statistics Field Description Received Transmitted Forwarded Hdr Errors Hop Count Errors Addr Errors No Routes Misc Errors NetBIOS Rx NetBIOS Tx NetBIOS Max Hops Host Rx Host Tx Number of IPX forwarding packets received Number of IPX forwarding packets transmitted Number of IPX packets forwarded by the IPX router Number of IPX packets dropped due to IPX Network layer header errors Number of IPX packets dropped due to exceeded maximum transport control Number of IPX packet dropped due to IPX Address errors in network layer header Number of IPX packets dropped because the IPX route is unknown Number of multicasts attempted to be forwarded Number of IPX NetBIOS packets received Number of IPX NetBIOS packets transmitted Number of IPX NetBIOS packets that exceeded the transport control maximum Number of IPX packets delivered to the IPX host s RIP and SAP applications Number of IPX packets transmitted from IPX host s RIP and SAP applications ADMINISTERING APPLETALK ROUTING This chapter describes how to set up your LANplex system to use the AppleTalk protocol to route packets For more informat
104. le VLANs For example you can assign port 1 on a LANplex to several IP subnet VLANs plus one IPX VLAN one AppleTalk VLAN and one NetBIOS VLAN In a multiprotocol environment protocol sensitive VLANs can be very effective for controlling broadcast and multicast flooding Two or more types of VLANs can coexist in the LANplex system When associating received data with a particular VLAN configuration in a multiple VLAN configuration port group MAC address group and application oriented VLANs always take precedence over protocol sensitive VLANs The LANplex protocol sensitive VLAN configuration includes three elements protocol suite switch ports layer 3 addressing information for IP VLANs Protocol Suite The protocol suite describes which protocol entities can comprise a protocol sensitive VLAN For example LANplex VLANs support the IP protocol suite which is made up of the IP ARP and RARP protocols Table 2 1 lists the protocol suites that the LANplex supports as well as the protocol types included in each protocol suite Table 2 1 Supported Protocols for VLAN Configuration Protocol Suite Protocol Types IP IP ARP RARP Ethertype SNAP PID Novell amp IPX IPX Ethertype DSAP SNAP PID AppleTalk amp DDP AARP Ethertype SNAP PID Xerox XNS XNS IDP XNS Address Translation XNS Compatibility Ethertype SNAP PID DECnet DEC MOP DEC Phase IV DEC LAT DEC LAVC Ethertype SNAP PID SNA SNA Services over Ethe
105. lly assigned 48 bit addresses used by Ethernet and token ring To make the address mapping process easier AARP uses an Address Mapping Table AMT The most recently used addresses are maintained in the AMT If an address is not in the AMT AARP sends a request to the desired protocol address and the hardware address is added to the table when the destination node replies AARP is also responsible for registering a node s dynamically assigned address on the network This process is described below AARP randomly assigns an address AARP broadcasts AARP probe packets to this address to determine if another node is already using the address If there is no reply the address becomes that node s address If there is a reply AARP repeats this process until an available address is discovered In the Administration Console you can Display the cache Remove entries Flush the cache Displaying the AARP Cache Top Level Menu System ethernet interface fddi Toute M display atm aarp remove bridge zone flush ip forwarding ipx checksum b appletalk ping snmp statistics analyzer script logout You can display the AARP cache for the system to determine which routes CHAPTER 12 ADMINISTERING APPLETALK ROUTING are configured and if they are operational To display the contents of the AARP cache From the Administration Console top level menu enter appletalk aarp display The following example shows an AARP
106. mments about this document to 3Com at sdtechpubs_comments 3Mail 3Com com Please include the following information when commenting Document title Document part number listed on back cover of document a Page number if appropriate Example LANplex 2500 Operation Guide Part No 801 00344 000 Page 2 5 chapter 2 page 5 LANPLEX EXTENDED SWITCHING FEATURES This chapter provides an overview of the Extended Switching software and describes the enhanced Administration Console menus About LANplex Extended Switching The LANplex Extended Switching software replaces your existing LANplex software and adds new functionality to your system Extended Switching software contains all the features of LANplex Intelligent Switching software in addition to Virtual LANs VLANs Internet Protocol IP Routing an enhanced version of IP from the standard system software IP multicast routing Classical IP routing over Asynchronous Transfer Mode ATM Internet Packet Exchange IPX routing AppleTalk routing Remote Monitoring RMON For information on how to gain access to online help to use scripts and to exit from the Administration Console see the LANplex 2500 Administration Console User Guide See the LANplex 2500 Software Installation and Release Notes for information about how to install Extended Switching software on your LANplex system 1 2 CHAPTER 1 LANPLEX EXTENDED SWITCHING FEATURES Using Men
107. n the system you must define at least one IPX interface See the section Defining an IPX Interface on page 11 3 Static routes remain in the table until you remove them or until you remove the corresponding interface Static routes take precedence over dynamically learned routes to the same destination You can set up to 16 static routes To define a static route From the Administration Console top level menu enter ipx route static Enter the 4 byte IPX network address of the route Enter the cost of the route Enter the interface number of the route Administering Routes 11 7 5 Enterthe node address of the route A static route is defined in the following example Enter IPX address 0x45469f30 Enter Cost 1 Enter Interface number 1 Enter node address 08 00 3e 22 15 78 Removing a Route To remove a route Top Level Menu 1 From the Administration Console top level menu enter system ethemet interface fddi route display ipx route remove atm Server static ridge forwarding pud 2 Enter the 4 byte IPX network address np usl Pie J enhanced The route is immediately deleted from the routing table appletalk sap snmp statistics analyzer script logout Flushing Routes Flushing deletes all dynamically learned routes from the routing table To flush all learned routes from the Administration Console top level menu enter Top Level Menu ipx route flush System iemet rae TE All
108. ndex 2 Do you wish to continue yes no yes Accept the default yes if you want to delete the interface CHAPTER 9 ADMINISTERING IP ROUTING Adding an Advertisement Menu Top Level system etheme fddi atm bridge Dip ipx appleta snmp analyze script logout P interfaq Toute arp atmArp multica udpHel routing icmpRo rip ping statistics Address summary detail define modify 2 remove M addAdvertisement removeAdvertisement 3 addPvc removePvc Removing an Advertisement Menu Top Level System ethern fddi atm bridge b ip ipx appleta snmp analyzel script P interface Toute arp atmArp multica udpHel routing Address summary detail define modify 2 remove addAdvertisement icmpRoll removeAdvertisement rip ping logout statistics addPvc removePvc This command adds an advertisement address to the advertisement address list associated with the interface To add an advertisement address From the top level of the Administration Console enter ip interface addAdvertisement Enter the interface index number Enter the advertisement address separated by commas Example Select interface index 1 1 Enter advertisement address 158 101 255 1 158 111 1 1 This command removes an advertisement address from the advertisement address list associated with the interface To remove an advertisement address From the top leve
109. ned if you do not want layer 3 addressing Removing VLAN Information 8 5 Example Select menu option bridge vlan modify Select VLAN interface 1 2 2 Protocol Suite IP IPX AppleTalk XNS DECnet SNA Banyan X 25 NetBIOS NetBEUI default AppleTalk IP VLAN Identifier 1 2 VLAN Name Sales Ports 1 FDDI 2 17 Ethernet Enter port s 1 17 all 1 5 Layer 3 Address undefined defined undefined Removing VLAN Follow these steps to remove a VLAN definition Information 1 From the top level of the Administration Console enter Top Level Menu System bridge vlan remove ethernet fddi display atm mode 2 Enterthe indexes for the VLANs you want to remove bridge ipFragmentation ip ipxSnapTranslation ipx addressThreshold Example appletalk agingTime snmp stpState analyzer stpPriority summary Select menu option bridge vlan remove script stpMaxAge detail Select VLAN index es 1 2 all 1 logout stpHelloTIme define stpForwardDelay modify StpGroupAddress port packetFilter vlan remove 8 6 CHAPTER 8 ADMINISTERING VLANS ADMINISTERING IP ROUTING This chapter describes how to set up your LANplex system to use the Internet Protocol IP For more information about how IP works see Part III of this guide You can display or configure the following IP characteristics on your LANplex system IP interfaces Routes Address Resolution Protocol ARP cache
110. nes both the number of the network to which the interface is attached and the interface s host number on that network Subnet Mask A subnet mask is a 32 bit number that uses the same format and representation as IP addresses The subnet mask determines which bits in the IP address are interpreted as the network number the subnet number and the host number Each IP address bit corresponding to alin the subnet mask is in the network subnet part of the address Each IP address bit corresponding to a 0 is in the host part of the IP address m Advertisement Address The switching module uses this IP address when it advertises routes to other stations on the same subnet In particular the system uses this address for sending RIP updates By default the switching module uses a directed advertisement all 1s in the host field Cost This number between 1 and 15 is used when calculating route metrics Unless your network has special requirements assign a cost of 1 to all interfaces Type The P interface is one of these types VLAN which supports routing between two VLANs LIS which supports classical IP over ATM m State This status of the IP interface indicates whether the interface is available for communications VLAN Interface When you select VLAN as the interface type the Administration Console prompts you for the VLAN index number The VLAN index number indicates which bridge ports are associated with
111. net SNA Banyan X 25 NetBIOS NeBEUI default IP Enter VLAN Identifier 1 Enter VLAN Name SD Marketing Ports 1 FDDI 2 17 Ethernet Enter port s 1 17 al1 1 5 Layer 3 Address undefined defined defined Enter IP Subnet Address 158 111 122 0 Enter subnet mask 255 255 0 0 255 255 255 0 The maximum number of VLANs you can define on a single bridge is 32 Modifying VLAN Information Top Level Menu System ethemet fddi atm bridge ip ipx appletal snmp analyzer script logout display mode ipFragmentation ipxSnapTranslation Threshold agingTime address stpState stpPriori StpMaxAt stpHello stpForwardDelay port packetFi vlan summary detail define stpGroupAddress f modify remove To modify VLAN information From the top level of the Administration Console enter bridge vlan modify You are prompted to reenter the information that defines the VLAN Press the Return or Enter key to accept any value that appears in brackets Enter the number of the VLAN interface index Enter the protocol suite for that VLAN IP IPX AppleTalk XNS DECnet SNA Banyan X 25 NetBIOS NetBEUI default Enter the VLAN identifier Enter the VLAN name Enter the number s of the port s or all If you have selected the IP protocol suite and want to use the Layer 3 address information enter defined for layer 3 addressing Enter undefi
112. nts share the same switch ports yet the IP and IPX traffic stays separate See Figure 2 2 VLAN 1 IP IP Server VLAN 1 VLAN 2 IPX VLAN 1 IP VLAN 2 IPX Fast Ethernet IPX 100 BASEt IPX IPX IPX Server VLAN 2 Figure 2 2 A VLAN Configuration with Servers on Separate 100BASE T ports 2 12 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM BRIDGING AND ROUTING IN THE LANPLEX SYSTEM This chapter shows how the LANplex system operates in a subnetworked routing environment and describes the LANplex routing methodology specifically how the LANplex bridging and routing model compares with traditional models What Is Routing Routing is the process of distributing packets over potentially dissimilar networks A router also called a gateway is the machine that accomplishes this task Routers are typically used to Connect enterprise networks together Connect subnetworks or client server networks to the enterprise network Figure 3 1 shows where routers are typically used in a network The LANplex system performs routing that connects subnets to the enterprise network providing connectivity between devices within a workgroup department or building Sales Connecting enterprise networks Router
113. ole polls network devices constantly to determine if the network is within its normal operating conditions As network size and traffic levels grow however the network management console can become overburdened by the amount of data it must collect Frequent console polling also generates significant network traffic that itself can create problems for the network itself An RMON implementation offers solutions to both of these problems The RMON probe looks at the network on behalf of the network management console without affecting the characteristics and performance of the network itself The RMON MIB reports by exception rather than by sending constant or frequent information to the network management console The RMON probe informs the network management console directly if the network enters an abnormal state The console can then use more information from the probe such as history information to diagnose the abnormal condition LANplex RMON Implementation gt The LANplex Extended Switching software offers full time embedded RMON support through SNMP for four RMON Groups When combined with the Roving Analysis Port RAP function RMON support for these groups provides a comprehensive and powerful mechanism for managing your network You can gain access to the RMON capabilities of the LANplex 2500 system only through SNMP applications such as Transcend GEnterprise Manager software not through the serial interface or telne
114. on equals one hop Selecting the Best Route Large networks have multiple routes to a single network The routers use these criteria to select the best route to a network when choosing between alternate routes Select the route that requires the lowest number of ticks If multiple routes exist with an equal number of ticks select the route that also has the lowest number of hops If multiple routes exist with both ticks and hops equal choose any of the routes as the best route The Service Advertising Protocol SAP allows servers for example file servers print servers and gateway servers to advertise their addresses and services Through the use of SAP adding and removing services on an internetwork becomes dynamic As servers are booted up they advertise their services using SAP When they are brought down they use SAP to indicate that their services are no longer available Internetwork Service Information Using SAP routers create and maintain a database of internetwork service information Clients on use this data to determine what services are available on the network and to obtain the internetwork address of the nodes servers where they can access desired services IPX Packet Format IPX Header 30 bytes Packet Type 4 Socket 452h The Elements of IPX Routing 6 11 A workstation must first know a server s network address before it can initiate a session with a file server SAP Packet Structure S
115. one invalid bit set in response to a GetNetInfo request with an invalid zone name outAddrinvs Number of times this entity had to broadcast a ZIP GetNetInfo reply because the GetNetInfo request had an invalid address The NBP handles the translations between the numeric internet address and the alphanumeric entity names used by AppleTalk To display NBP statistics From the Administration Console top level menu enter appletalk statistics nbp An example of summary statistics is shown below gt forwarding is enabled inLkupReqgs inBcastReqs inFwdReqs inLkupReplies 3093 611 5951 0 inErrors 0 12 18 CHAPTER 12 ADMINISTERING APPLETALK ROUTING Table 12 4 describes the NBP statistics you can view Table 12 4 NBP Statistics Field Description inLkupReqs Number of NBP Lookup Requests received inBcastsReqs Number of NBP Broadcast Requests received inFwdReqs Number of NBP Forward Requests received inLkupReplies Number of NBP Lookup Replies received inErrors Number of NBP packets received that were rejected for any error REMOTE MONITORING RMON V AND THE LANPLEX SYSTEM Stt v Pesce Chapter 13 Remote Monitoring RMON Technology 13 oe tte es ss REMOTE MONITORING RMON TECHNOLOGY This chapter provides an overview of RMON and describes the specific LANplex RMON implementation What Is RMON The Remote Monitoring RMON Management Information Base MIB prov
116. ost Configuration Protocol that rely on the BOOTP relay agent For example by configuring the logical BOOTP port you can boot hosts through the router UDP Helper also provides a relay agent for DHCP broadcasts UDP packets that rely on the BOOTP relay agent are modified and then forwarded through the router The following ports for the UDP services are mentioned in this section on UDP Helper BOOTP including DHCP 67 TIME 37 DNS 53 UDP Helper allows you to configure the amount of time a UDP packet is forwarded between subnetworks UDP packets are discarded based on the hop count and the seconds value only for BOOTP and DHCP Displaying UDP Helper Information Top Level Menu System ethemet fddi atm bridge b ip ipx appletalk snmp analyzer script logout interface route arp atmArpServd remove multicast hopCountLimit DudpHelper threshold routing icmpRouterDiscovery rip ping statistics Defining a Port and an IP Forwarding Address Top Level Menu system ethernet fddi atm bridge b ip ipx b udpHelper appletalk snmp analyzer script logout interface route display arp define atmArpServd remove multicast hopCountLimit threshold routing icmpRouterDiscovery rip ping statistics Removing a Port or an IP Forwarding Address Top Level Menu system ethemet fddi atm bridge dip ipx appletalk snmp analyzer script logout interface
117. otocols 7 5 AppleTalk Piling PostScript Protocol AFP AppleTalk Data Stream Protocol ADSP AppleTalk Session Protocol ASP Printer Access Protocoo PAP Zone Information Protocol ZIP quen pnm AppleTalk Transaction Protocol ATP Routing Table Maintenance Protocol RTMP Name Binding Protocol NBP AppleTalk Echo Protocol AEP Datagram Delivery Protocol DDP LocalTalk amp Link Access Protocol TokenTalk Link Access Protocol EtherTalk Link Access Protocol Token Ring Ethernet LocalTalk Hardware Hardware Hardware The AppleTalk six layer protocol suite is not fully compliant with the OSI seven layer reference model However AppleTalk provides many of the functions and services provided by OSI Note that AppleTalk has no specific protocols for the application layer since the lower levels provide printer and file service Physical Connectivity The physical layer of the OSI protocol stack defines the network hardware You can use standard network hardware such as that defined for Ethernet and Token Ring networks with AppleTalk Apple has also defined its own network hardware called LocalTalk which uses a synchronous RS 422A bus for communications The data link layer provides the interface between the network hardware and the upper layers of the protocol
118. outer Discovery enabling 9 21 IGMP about 5 1 enabling 10 2 interface administering an IP multicast 10 3 defining an IP 9 6 defining an IP multicast 10 2 interface AppleTalk defining an 12 3 displaying an 12 3 removing an 12 4 interface IP defining a LIS 9 4 defining a VLAN 9 6 displaying an 9 3 parts of 9 1 removing definition 9 7 interface IP multicast disabling 10 5 displaying 10 4 enabling 10 5 parts of 10 1 interface IPX defining an 11 3 displaying an 11 3 modifying an 11 4 removing an 11 4 Interior Gateway Protocols IGP 4 6 6 9 Internet address See IP address Internet Control Message Protocol See ICMP Internet Protocol See references with IP address intranetwork routing diagram 3 2 IP address translation 9 13 ARP cache 9 13 enabling routing 9 20 interface 9 1 main menu 1 4 pinging astation 9 22 RIP mode 9 21 9 22 route displaying table 9 11 routes 9 9 statistics displaying 9 23 IP address classes of 4 3 defined 4 2 derived from 4 2 division of network and host 4 2 example 4 4 network layer and the 4 1 RIP and 4 6 routing table and the 4 5 subnet mask and the 4 3 subnet part 4 3 IP interface defining 9 6 displaying 9 3 removing definition 9 7 IP mulitcast routing interface disabling 10 5 IP multicast cache displaying 10 9 routes displaying 10 8 IP Multicast menu 1 4 IP multicast routing about 5 1 algorithms 5 3 interfaces 10 1 administering 10 3 defining
119. p rip M ipx enhanced appletalk Sap snmp statistics analyzer script logout Server display V static remove flush Administering Servers 11 9 You can display the server table for the system to determine which servers are learned and if they are operational To display the contents of the server table from the Administration Console top level menu enter ipx server display IPX forwarding is enabled RIP is active SAP is active Name Type Network Node Socket Hops Age GB201 39b 8cl41bf 08 00 02 04 80 b6 8059 4 73 GB3COM2 39b af0bc60f 00 00 00 00 00 01 85fa 4 85 Before you define static servers on the system you must define at least one IPX interface See the section Defining an IPX Interface on page 11 3 Static servers remain in the table until you remove them or until you remove the corresponding interface Static servers take precedence over dynamically learned servers to the same destination You can have a maximum of eight static servers To define a static server From the Administration Console top level menu enter ipx server static Enter the interface number of the server Enter the service type of the server Enter the service name of the server Enter the IPX network address of the server Enter the socket value of the server Enter the node address of the server 11 10 CHAPTER 11 ADMINISTERING IPX ROUTING 8 Removing a Server Top Level Menu 1 System ethemet
120. port stpState Italic Italic is used to denote emphasis and buttons Keys When specific keys are referred to in the text they are called out by their labels such as the Return key or the Escape key or they may be shown as Return or Esc If two or more keys are to be pressed simultaneously the keys are linked with a plus sign 4 for example Press Ctrl Alt Del LANplex 2500 The following documents comprise the LANplex 2500 documentation set Documentation If you want to order a document that you do not have or order additional documents contact your sales representative for assistance m LANplex 2500 Unpacking Instructions Describe how to unpack your LANplex system It also provides you with an inventory list of all the items shipped with your system Shipped with system Part No 801 00353 00 LANplex 2500 Software Release Notes Provide information about the software release including new features and bug fixes It also provides information about any changes to the LANplex system s documentation Shipped with system LANplex 2500 Getting Started Describes all the procedures necessary for installing cabling powering up configuring management access to and troubleshooting your LANplex sys tem Shipped with system Part No 801 00355 000 LANplex 2500 Operation Guide Provides information to help you understand system management and administration bridging Fast Ethernet ATM and FDDI technology
121. r see the following section on how to contact 3Com A 4 APPENDIX A TECHNICAL SUPPORT Support from If you are unable to receive support from your network supplier technical 3Com support contracts are available from 3Com In the U S and Canada call 800 876 3266 for customer service If you are outside the U S and Canada contact your local 3Com sales office to find your authorized service provider Use one of these numbers Country Telephone Number Country Telephone Number Australia 1800678515 Jaan 80 3349 251 Mexico 525 531 0591 Belgium 0800 71429 Netherlands 06 0227788 Brazil 55 11 546 0869 Norway 800 11376 Canada 416 498 3266 Singapore 65 538 9368 Denmark 800 17309 South Africa 27 11 803 7404 Finland 0800 113153 Spain 900 983125 France 05 917959 Sweden 020 795482 Germany 0130 821502 Taiwan 886 2 577 4352 Hong Kong 852 2501 1111 United Arab Emirates 971 4 349049 Ireland 1800 553117 U K 0800 966197 Italy 1678 79489 U S 1 408 492 1790 These numbers are toll free Returning Products Before you return a product directly to 3Com for repair you must first call for Repair for a Return Materials Authorization RMA number A product sent to 3Com without an RMA number will be returned to the sender unopened at the sender s expense To obtain an RMA number call or fax Country Telephone Number Fax Number U S and Canada 800 876 3266 option 2 408 764 71
122. r if the value has not fallen below the low threshold before rising above the high threshold The counter value exceeds the low threshold after previously exceeding the high threshold An alarm does not occur if the value has not risen above the high threshold before falling below the low threshold In Figure 13 3 for example an alarm occurs the first time the counter exceeds the high threshold but not at the second time At the first instance the counter is rising from the low threshold while in the second instance it is not APPENDIX AppendixA Technical Support otto e e eee TECHNICAL SUPPORT 3Com provides easy access to technical support information through a variety of services This appendix describes these services On line Technical Services 3Com Bulletin Board Service 3Com offers worldwide product support 24 hours a day seven days a week through the following on line systems 3Com Bulletin Board Service 3ComBBS World Wide Web site 3ComForum on CompuServe online service 3ComFacts automated fax service 3ComBBS contains patches software and drivers for all 3Com products as well as technical articles This service is available via analog modem or ISDN 24 hours a day seven days a week Access by Analog Modem To reach the service by modem set your modem to 8 data bits no parity and 1 stop bit Call the telephone number nearest you Country Data Rate T
123. ransmitted over the VLAN outBytes Number of flooded broadcast and multicast bytes transmitted over the VLAN Defining VLAN Information Top Level Menu System ethemet fddi display atm mode bridge ipFragmentation ip ipxSnapTt ipx addressThreshold appletalk agingTime snmp stpState analyzer stpPriority script stpMaxAge logout stpHelloTime stpForwardDela P defne stpGroupAddre port packetFi vlan Follow these steps to create a VLAN definition From the top level of the Administration Console enter bridge vlan define Enter the appropriate protocol suite 1P IPX AppleTalk XNS DECnet SNA Banyan X 25 NetBIOS NetBEUI default Enter the VLAN interface identifier Enter the VLAN name enclosed in quotation marks Enter the number s of the port s or a11 to assign all ports to the VLAN You are prompted to enter the number s of the port s that can be assigned to the VLAN If you did not choose the IP protocol suite for this VLAN you have completed the steps for defining the VLAN If you selected the IP protocol suite follow these steps Enter defined to use layer 3 subnet addressing and continue with steps 2 and 3 OR enter undefined to not use layer 3 addressing Enter the IP subnet address Enter the subnet mask CHAPTER 8 ADMINISTERING VLANS gt Example Select menu option bridge vlan define Enter Protocol Suite IP IPX AppleTalk XNS DEC
124. removing a 11 7 router interface IP described 4 4 diagram 4 5 routing table and the 4 5 router interface IPX described 6 8 routers seed 7 4 routes displaying IP multicast 10 8 routing and bridging in switching modules 3 4 and bridging traditional model 3 4 implementation in LANplex 3 4 LANplex system and the 3 1 to 3 7 See also IP routing IPX routing and AppleTalk routing Routing Information Protocol See RIP routing table display routes 9 11 routing table AppleTalk 7 8 routing table IP contents 4 5 9 9 default route 4 7 default route setting 9 13 described 4 5 dynamic routes 4 6 example 4 6 flushing learned routes 9 12 metric 4 5 removing default route 9 13 removing route 9 12 static routes 4 6 routing table IPX contents 6 8 described 6 8 displaying 11 6 dynamic routes 6 9 example 6 9 flushing learned routes 11 7 removing a route 11 7 static routes 6 9 RTMP description of 7 6 INDEX 5 S SAP aging mechanism 6 14 packet structure 6 11 request handling 6 15 using for dynamic routes 6 14 SAP mode setting 11 13 SAP statistics displaying 11 16 seed routers 7 4 segmentation increasing 3 3 server 9 4 9 16 defining a static IPX 11 9 server table contents 6 13 described 6 13 displaying 11 9 Service Advertisement Protocol See SAP session layer protocols AppleTalk 7 9 software installation 1 1 static route IP 4 6 status of 9 10 static route IPX 6 9 defining 11 6 static server IPX defining
125. ress from the ATM ARP server If the address is known to the server the server returns a message with this address If the address is not known to the server the server returns a message to advise the sending node that the packet is discarded When the server returns a destination address the sending node uses this learned address to create a virtual circuit VC and to forward this and all subsequent packets to the destination address The sending node adds this VC to its ATM ARP cache IP Routing References Comer Douglas E Internetworking with TCP IP Volume I Principles Protocols and Architecture Englewood Cliffs New Jersey Prentice Hall Inc 1991 Perlman Radia Interconnections Bridges and Routers Reading Massachusetts Addison Wesley Publishing Company Inc 1992 Sterns Richard TCP IP Illustrated Volume 1 The Protocols Reading Massachusetts Addison Wesley Professional Computing Services 1992 RFC 791 Internet Protocol Specification RFC 792 Internet Control Message Protocol Specification RFC 1009 Requirements for Internet Gateways RFC 1042 A Standard for the Transmission of IP Datagrams over IEEE 802 Networks RFC 1058 Routing Information Protocol RFC 1122 Requirements for Internet Hosts RFC 1577 Classical IP over ATM 4 12 CHAPTER 4 ROUTING WITH IP TECHNOLOGY oe tte es ss ROUTING WITH IP MULTICAST This chapter describes the IP multicast routing implementat
126. rface in kilobytes per second The LANplex system drops multicast traffic that travels faster than this rate The default is set to 0 which implies no rate limit is set In all other instances the lower the rate limit the more limited the traffic over the interface Multicast Tunnels Multicast tunnels are logical connections between two multicast routers through one or more unicast routers The multicast router at the local endpoint of the tunnel encapsulates multicast packets in a format that unicast routers can interpret and forward The multicast router at the remote endpoint decapsulates the packets into their multicast format Tunnels are virtual links through the unicast IP network Multicast tunnels have characteristics similar to those of a multicast interface a DVMRP metric value a TTL threshold and a rate limit When you define a multicast tunnel you also specify the destination address of the remote multicast router that is the remote endpoint of the tunnel oe tte ess ROUTING WITH IPX This chapter provides an overview of IPX routing including What part IPX plays in the NetWare environment How IPX works What elements are necessary for IPX routers to transmit packets effectively IPX Routing in the NetWare Environment The NetWare network operating system was developed and introduced to the market by Novell Inc in the early 1980s Much of the NetWare networking technology was derived from
127. rip ping statistics By default RIP operates in passive mode To set the RIP operating mode From the top level of the Administration Console enter ip rip Enter the RIP mode off passive Of active To use the value in brackets press Return at the prompt Example Select RIP mode active off passive active passive Pinging an IP Station Top Level Menu system ethemet fddi atm bridge bip ipx appletalk snmp analyzer script logout interface Toute arp atmArpServer multicast udpHelper routing icmpRouterDiscovery rip V ping statistics Pinging uses the Internet Control Message Protocol ICMP echo facility to send an ICMP echo request packet to the IP station you specify It then waits for an ICMP echo reply packet Possible responses from pinging Alive No answer Network is unreachable A network is unreachable when there is no route to that network To ping an IP station From the top level of the Administration Console enter ip ping Enter the IP address of the station you want to ping IP Address 192 9 200 40 You may receive one of the following responses 192 9 200 40 is alive OR no answer from 192 9 200 40 For a remote IP address you can also receive the following response Network is unreachable Displaying IP Statistics 9 23 Displaying IP Statistics Top Level Menu System ethernet fddi atm bridge bip ipx appletalk snmp analyzer
128. rk segment s identity This element allows the physical segment between two LANplex systems to be a range of multiple networks Address The AARP address based on the network range and the network node 1 253 Zone The default zone name as well as up to 15 additional defined zones State This is the status of the AppleTalk interface which indicates whether the interface is available for communications up or unavailable down VLAN Index The number of the AppleTalk VLAN associated with the AppleTalk interface The VLAN index indicates which bridge ports are associated with the AppleTalk interface When the menu prompts you for this option it displays a list of available VLAN indexes and their ports Displaying AppleTalk Interfaces Top Level Menu System ethemet interface fddi route I display atm aarp define bridge zone remove ip forwarding ipx checksum M appletalk ping snmp statistics analyzer script logout Defining an Interface Top Level Menu System ethemet B interface fddi route display atm aarp M define bridge zone remove ip forwarding ipx checksum M appletalk ping snmp statistics analyzer script logout 12 3 Administering Interfaces You can display a table that shows all AppleTalk interfaces and their parameter settings configured for the system To display the AppleTalk interfaces defined on the router from the Administration Console top level menu enter
129. rnet Ethertype Banyan VINES Banyan Ethertype DSAP SNAP PID continued CHAPTER 2 VLANS ON THE LANPLEX SYSTEM Table 2 1 Supported Protocols for VLAN Configuration continued Protocol Suite Protocol Types X25 X25 Layer 3 Ethertype NetBlOS NetBIOS DSAP Default Default all protocol types Switch Ports A group of switch ports is any combination of switch ports on the LANplex system Included are switch ports created as ATM LAN Emulation Clients ATM LECs VLANs do not support media implementations that do not run over switch bridge ports for example ATM Logical IP Subnets ATM LISs Layer 3 Addressing Information For IP VLANs only the LANplex system optionally supports configuring of individual IP VLANs with network layer subnet addresses With this additional layer 3 information you can create independent IP VLANs that share the same switch ports for multiple IP VLANs Data is flooded according to both the protocol IP and the layer 3 information in the IP header to distinguish among multiple IP VLANs on the same switch port This configuration is discussed later in the section Overlapped IP VLANs Default VLAN gt How the LANplex System Makes Flooding Decisions About VLANs 2 5 When you start up the LANplex system the system automatically creates a VLAN interface called the default VLAN Initially the default VLAN includes all of the switch ports in the system In the LANplex system
130. rnet Packet Exchange IPX protocol to route packets For more information about how IPX works see Part Ill of this Guide You can display and configure the following on your LANplex system IPX interfaces Routes Servers IPX forwarding Routing Information Protocol RIP Enhanced RIP mode Service Advertising Protocol SAP IPX statistics 11 2 CHAPTER 11 ADMINISTERING IPX ROUTING Administering Interfaces An IPX interface defines the relationship between an IPX Virtual LAN VLAN and the IPX network Every IPX interface has one IPX VLAN associated with it Each switching module has one IPX interface defined for each subnet directly connected to it You must first define a VLAN as described in Chapter 8 Administering VLANs before you define an associated interface An IPX interface has the following information associated with it IPX network address The network administrator sets this 4 byte address Each address within the network should be unique Cost This number between 1 and 15 is used when calculating route metrics Unless your network has special requirements such as the need for redundant paths you should assign a cost of 1 to each interface Encapsulation format IPX routing uses four Ethernet encapsulation formats and two FDDI encapsulation formats The Ethernet encapsulation formats are Ethernet Type Il Novell 802 3 raw 802 2 LLC and 802 3 SNAP The FDDI encapsulation formats are FDDI 802 2
131. rol field in the IPX header and sends the packet to the next router 6 8 CHAPTER 6 ROUTING WITH IPX The Elements of IPX Routing Router Interfaces Routing Tables IPX routers use the following elements to transmit packets over an intranetwork Router interfaces Routing tables Service Advertising Protocol SAP A router interface is the connection between the router and the network number address In traditional routing models the interface would be the same as the port because only one interface can exist per port In the LANplex system s IPX routing more than one port can be connected to the network number Therefore the router interface is the relationship between the ports and the network number address in your IPX network Each router interface has a network address This address defines the network number to which the router interface is attached The router interface s IPX address serves two functions It is used when sending IPX packets to or from the router itself It defines the network number of the segment connected to that interface A routing table holds information about all the network segments It allows a router to send a packet toward its ultimate destination using the best possible route The routing information table contains an entry for every network number that the router currently knows exists A router uses the routing information table when the destination network number of the packet it is
132. rrors Number of DDP datagrams which were dropped because of a checksum error inBcastErrors Number of DDP datagrams for which this DDP entity was their final destination and which were dropped because of a broadcast error inTooFars Number of input datagrams dropped because this entity was not their final destination and their hop count would exceed 15 inDiscards Number of DDP Datagrams thrown out during the routing process outLocals Number of host generated DDP datagrams To display RTMP statistics From the Administration Console top level menu enter appletalk statistics rtmp An example of summary statistics is shown below DDP forwarding is enabled inDatas inRequests outDatas outRequests 7204 0 4865 6 routeEqChgs routeLessChgs routeDeletes routeOverflows 0 0 0 0 inVersionErrs inOtherErrs 0 119 Table 12 2 describes the RTMP statistics you can view Displaying ZIP Information Top Level Menu System ethernet fddi M appletalk snmp analyzer script logout interface route ddp aarp itmp zone forwarding T checksum p ping statistics 12 15 Viewing Appletalk Statistics Table 12 2 RTMP Statistics Field Description inDatas Number of good RTMP data packets received inRequests Number of good RTMP request packets received outDatas Number of good RTMP data packets sent outRequests Number of RTMP request packets sent routeEqChgs Number of times RTMP changes the Next Internet Router
133. rs and the ATM port number The other prompts do not appear because you do not enter an ATM ARP server address If you define both SVCs and PVCs enter all LIS interface information You can display both summary and detailed information about all IP interfaces configured for the system The detail display contains all the summary information as well as information about the advertisement address PVCs and VLANs To display IP interface information enter one of the following command strings from the Administration Console top level menu ip interface summary OR ip interface detail CHAPTER 9 ADMINISTERING IP ROUTING Example summary display IP routing is enabled RIP is active ICMP discovery is disabled Index Type IP address Subnet mask Cost State VLAN Index 1 VLAN 158 101 1 1 255 255 255 0 1 Down 2 Index Type IP address Subnet mask Cost State Port 2 LIS 158 I01 112 lL 255 255 255 0 1 Up 1 Example detail display IP forwarding is enabled RIP is active ICMP discovery is disabled Index Type IP address Subnet mask Cost State VLAN index 1 VLAN 158 101 1 1 255 255 255 0 J Down 2 Index Type IP address Subnet mask Cost State Port 2 LIS 158 101 112 1 255 255 255 0 1 Up 1 4 Advertisement Addresses 158 101 112 200 158 101 112 203 158 101 112 204 158 101 112 205 atmArpServer 47 0000 00 000000 0000 0000 00cc 080001200054 ff maxSvcCount inactivityTime minHoldingTime 0 1200 60 IPVC 1 32 Defining an IP
134. s Multicast Tunnels to a destination router that supports multicast A tunnel has two end points The local end point is associated with an interface on the LANplex router When you define the tunnel you specify the associated index on the local LANplex router and then the characteristics of the tunnel Tunnel characteristics are the same as the those of an interface You also specify the IP address of the remote multicast router p Not all multicast configurations require a tunnel The only configurations that require a tunnel are those that require a connection between two multicast internetworks through one or more unicast routers Displaying To display the IP multicast tunnel s on the router from the top level menu Multicast Tunnels of the Administration Console enter ip multicast tunnel display Top Level Menu System ethernet interface fddi Toute dvmrp atm am igmp M display bridge atmArpS interface define dip M multicas tunnel remove ipx udpHelp routeDispiay appletalf routing cacheDisplay snmp icmpRouterDiscovery analyzer rip script ping Example IP multicast tunnel configuration logout statistics Index Local Address Remote Address Metric Threshold RateLimit State 1 158 101 112 204 137 39 229 98 2 255 500 pkts in 320069 pkts out 0 peers 137 39 229 98 3 8 0xe Administering Multicast Tunnels 10 7 Defining a To define an IP multicast tunnel Multicast Tunnel Top Level
135. s you need to define an ATM ARP server for each LIS Each LIS must connect to a single ATM network and must belong to the same IP subnet The atmarpserver menu also includes the arp option which allows you to administer the ATM ARP cache To display a list of ATM ARP servers from the top level of the Administration Console enter ip atmArpServer display Example icmpRouterDiscovery TP routing is enabled RIP is active ping ICMP router discovery is disabled Port IP Address Subnet Mask 1 T58 TOT T 1 255 255 2550 ATM address 47 0000 00 000000 0000 0000 00cc 000000000000 f f Defining an ATM ARP Server Menu Top Level System ethernd fddi atm bridge bip ipx appleta snmp analyze script logout interface Toute arp gt M atmArpServ a multicast remove udpHelper am routing icmpRouterDiscovery rip ping statistics Removing an ATM ARP Server Menu Top Level system ethernd fddi atm bridge bip ipx appleta snmp analyze script logout interface Toute arp display DatmArpServd define multicast remove udpHelper arp routing icmpRouterDiscovery rip ping statistics CHAPTER 9 ADMINISTERING IP ROUTING Determine the location of the ATM ARP server you want to use You can define the ATM ARP server externally on another LANplex system or on an ATM switch such as 3Com s CELLplex 7000 system To define an ATM ARP server from the top level of the Administra
136. s can appear in a list such as Laser1 or Laser 2 The Name Binding Protocol NBP described later in this chapter translates these device names into AppleTalk addresses AppleTalk amp Zones AppleTalk Network Elements 7 3 An AppleTalk zone is a logical collection of nodes on an AppleTalk internet A zone can include all nodes in a single network or a collection of nodes in different networks You assign a unique name to each zone to identify it in the internet Figure 7 1 illustrates the relationship between physical AppleTalk networks and logical AppleTalk zones Network 8 8 Network 20 40 Router i Zone Administration Router Network 47 47 Zone Accounting BH Router Zone Marketing Figure 7 1 AppleTalk Networks and AppleTalk Zones Figure 7 1 shows an AppleTalk internet with three networks 47 47 20 40 and 8 8 Three AppleTalk zones span the networks in this internet Administration Accounting and Marketing Network 20 40 includes two nodes in the Administration zone and five nodes in the Accounting zone Network 47 47 includes a node from the Accounting zone as well as the Marketing nodes Network 8 8 consists of nodes in the Administration zone only Creating zones within a network reduces the amount of searching a router has to do to
137. sending is not on a network to which it is directly connected The routing information table provides the immediate address of a forwarding router that can forward the packet toward its destination The routing table consists of the following elements Interface Identifies the number of the router s interface that will be used to reach the specific network segment Address Identifies the addresses for segments that the router currently knows exists The Elements of IPX Routing 6 9 Hops to Network Provides the number of routers that must be crossed to reach the network segment Ticks to Network Provides an estimate of the time necessary to reach the destination segment Node The node address of the router that can forward packets to each segment When set to all zeroes the route is directly connected Aging Timer The time since the network s last update Figure 6 4 shows an example of a typical routing information table Routing Table Interface Address Hops Ticks Node Age 1 1 00 00 00 00 00 00 0 45469f30 00 00 00 00 00 00 0 45469133 08 00 17 04 33 45 40 Figure 6 4 Routing Table Example Generating Routing Table Information The routing information table is generated and updated as follows Statically You manually enter routes They do not change until you change them they do not time out Dynamically The router uses RIP to exchange information with other routers Routes are recalc
138. ss in its ARP cache next to the corresponding IP address See Figure 4 8 ARP Cache IP Address MAC Address 158 101 1 1 00308e3d0042 158 101 2 1 0080232b00ab 158 101 3 1 0134650f3000 Figure 4 8 Example of ARP Cache Updated with ARP Reply Once the MAC address is known the host or router can send the packet directly to the next hop IP Routing Transmission Errors 4 9 IP Routing Transmission Errors Because each router only knows about the next hop it is not aware of problems that might be further down the road toward the destination Destinations can be unreachable if Hardware is temporarily out of service You inadvertently specified a nonexistent destination address The router does not have a route to the destination network To help routers and hosts know of problems in packet transmission an error reporting mechanism called Internet Control Message Protocol ICM P provides error reporting back to the source when routing problems arise ICMP allows you to determine whether a delivery failure resulted from a local or a remote malfunction ICMP does the following Tests the reachability of nodes ICMP Echo Request and ICMP Echo Reply A host or gateway sends an ICMP echo request to a specified destination If the destination receives the echo request it sends an ICMP echo reply back to the original sender This process tests whether the destination is reachable and responding and verifies that the major
139. stack The AppleTalk data link layer includes three link access protocols LAPs TokenTalk LAP TLAP Ethernet LAP ELAP and LocalTalk Link Access Protocol LLAP The AppleTalk Address Resolution Protocol AARP which translates hardware addresses to AppleTalk addresses also exists at the datalink layer 7 6 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT The Datagram Delivery Protocol DDP End to End Services because it is closely related to the Ethernet and token ring LAPs This protocol is usually included in the definition of each LAP so it does not appear in the reference model See the section About AARP later in this chapter for more information about this protocol The network layer accepts data from the layers above it and divides the data into packets that can be sent over the network through the layers below it The Datagram Delivery Protocol DDP transfers data in packets called datagrams Datagram delivery is the basis for building other AppleTalk services such as electronic mail The DDP allows AppleTalk to run as a process to process best effort delivery system in which the processes running in the nodes of interconnected networks can exchange packets with each other The transport layer and the session layer provide end to end services in the AppleTalk network These services ensure that routers transmit data accurately between one another Each layer includes four protocols that Work together to suppor
140. statistics with individual ports and then takes action based on these statistics For example the system can generate a log event and send an RMON trap if errors on a port exceed a user set threshold You must assign an IP address to the LANplex system to manage RMON See the LANplex 2500 Administration Console User Guide for information on how to assign an IP address Figure 13 1 shows an example of a LANplex RMON implementation The LANplex 2500 system in this figure has two Fast Ethernet connections in addition to the 10BASE T connections CHAPTER 13 REMOTE MONITORING RMON TECHNOLOGY Management console LAN LANplex 2500 system with embedded RMON probe Fast Ethernet ports i wo T7 Ethernet ports File Servers cy Ch cy g c Figure 13 1 Embedded RMON Implemented on the LANplex System Management Information Base MIB MIB Objects A MIB is a structured set of data that describes the way the network is functioning The management software known as the agent gains access to this set of data and extracts the information it needs The agent can also store data in the MIB The organization of a MIB allows a Simple Network Management Protocol SNMP network management package such as the Transcend Enterprise Manager application suite to manage a network device
141. stem first tries to bridge the packet If the packet s destination network address is not on the same subnet then the system routes the packet The bridge or router determines whether a packet should be bridged or routed based on the protocol to which the packet belongs If the packet belongs to a recognized protocol the packet is routed Otherwise it is bridged In the traditional bridging and routing model a packet is bridged as follows see Figure 3 4 The packet enters the bridge or router The bridge or router determines that the packet does not belong to a recognized routing protocol so the packet is passed to the bridge The bridge examines the destination MAC address and forwards the packet to the port on which that address has been learned Bridging and Routing Models 3 5 Router Bridge pm A y i y Io da Q Router vs Bridge o A Interfaces ports bad d ido m id i EE Networks re W MET Transmitting host Destination host Figure 3 4 Bridging in the Traditional Bridging and Routing Model In the traditional bridging and routing model a packet is routed as follows see Figure 3 5 1 The packet enters the bridge or router 2 The bridge or router determines that the packet belongs to a recognized routing protocol so the packet is passed to the router 3 The router examines the destination network address and forwards
142. t For more information about the details of managing 3Com devices using RMON see the user documentation of the Transcend Network Management Application for Windows The LANplex system supports four of the RMON groups defined by the IETF Table 13 1 lists these supported groups 3Com Transcend RMON Agents LANplex RMON Implementation 13 3 Table 13 1 RMON Groups Supported in the LANplex System Group Group Number Purpose Statistics 1 Maintains utilization and error statistics for the segment being monitored History 2 Gathers and stores periodic statistical samples from the statistics group Alarm 3 Allows you to define thresholds for any MIB variable and trigger an alarm Events 9 Allows you to define actions based on alarms You can generate traps log the alarm or both RMON requires one probe per LAN segment Because a segment is a portion of the LAN separated by a bridge or router the cost of implementing many probes in a large network can be high To solve this problem 3Com has built an inexpensive RMON probe into the Transcend SmartAgent software in each LANplex 2500 system This probe allows you to deploy RMON widely around the network at a cost no more than that for traditional network monitors Placing probe functionality inside the LANplex 2500 system has these advantages You can integrate RMON with normal device management The LANplex system can manage conditions proactively The LANplex system associates
143. t they update their own routing tables when they receive a RIP message The passive devices usually hosts listen for RIP messages and update their routing tables they do not send RIP messages Address Resolution Protocol ARP Elements of IP Routing 4 7 An active router sends a RIP message every 30 seconds This message contains both the IP address and a metric the distance to the destination from that router for each destination In RIP each router that a packet must travel through to reach a destination equals one hop Default Route In addition to the routes to specific destinations the routing table may contain an entry called the default route The router uses the default route to forward packets that do not match any other routing table entry A default route is often used in place of routes to numerous destinations all having the same gateway IP address and interface number The default route can be configured statically or it can be learned dynamically using RIP ARP is a low level protocol used to locate the MAC address correspond ing to a given IP address This protocol allows a host or router to make its routing decisions using IP addresses while it uses MAC addresses to forward packets from one hop to the next Once the host or router knows the IP address of the next hop to the destination the host or router must translate that IP address into a MAC address before the packet can be sent To do this translation th
144. t these services This section describes these protocols and provides more detail for those that you can view using the LANplex Administration Console Transport Layer Protocols An AppleTalk internet has four transport layer protocols Routing Table Maintenance Protocol RTMP AppleTalk Echo Protocol AEP AppleTalk Transaction Protocol ATP Name Binding Protocol NBP Routing Table Maintenance Protocol RTMP The protocol maintains information about AppleTalk addresses and connections between different networks It specifies that each router 1 learns about new routes from the other routers and 2 deletes routes after a certain period if the local router no longer broadcasts the route to the network AppleTalk Protocols 7 7 Each router builds a routing table that is the basis of dynamic routing operations in an AppleTalk internet Every 10 seconds each router sends an RTMP data packet to the network Routers use the information that they receive in the RTMP broadcasts to build their routing tables Each entry in the routing table contains these items The network range The distance in hops to the destination network The interface number of the destination network The state of each port good suspect bad really bad The router uses these items to determine the best path along which to forward a data packet to its destination on the network The routing table contains an entry for each network that a datagram can reach wi
145. tem ethemet interface fddi Toute atm aarp bridge zone ip forwarding ipx checksum b appletalk ping snmp statistics analyzer script logout 12 11 Configuring Forwarding Depending on the command entered the zone table is displayed by network or zone An example of each type of display is Shown below Zone Table by Network Numbers DDP forwarding is enabled etwork 1 1 has 1 known zone Munich GmbH etwork 3 has 1 known zone Ethernet A5D85800 etwork 10 14 has 1 known zone Freds Ethernet etwork 15 19 has 1 known zone Freds Token etwork 61 has 1 known zone DevMacNet etwork 100 100 has 1 known zone rance Les Ulis etwork 201 300 has 1 known zone Fred Wilma etwork 2010 2015 has 1 known zone Y etwork 10009 10009 has 2 known zones Hemel NSOPS 3Com Arpeggio etwork 10010 10010 has 1 known zone Marlow EUR Zone Table by Zones DDP forwarding is enabled Zone Holmdel is assigned to 2 networks 21105 21105 21010 21010 Zone NY is assigned to 2 networks 63535 63535 2010 2015 Zone Manchester UK is assigned to 1 network 10310 10329 Zone DC8 is assigned to 1 network 30110 30129 Zone Chicago is assigned to 1 network 22030 22030 Zone Startek Enetl is assigned to 1 network 20033 20033 Zone Startek TR1 is assigned to 1 network 20037 20037 Zone Test GmbH is assigned to 1 network 12010 12012 Zone Madrid3Com is assigned to 1 network 14010 14029 Zone NSDEng is assigned to
146. the packet to the interface port connected to the destination subnet Router Bridge 9 X Denr Router vs Bridge PL Interfaces ports Networks Av Transmitting host Destination host Figure 3 5 Routing in the Traditional Bridging and Routing Model 3 6 CHAPTER 3 BRIDGING AND ROUTING IN THE LANPLEX SYSTEM LANplex Bridging The LANplex 2500 system uses the destination MAC address to and Routing Model determine whether it will bridge or route a packet Before a host system sends a packet to another host it compares its own network address to the network address of the other host as follows If network addresses are on the same subnet the packet is bridged directly to the destination host s address If network addresses are on different subnets the packet must be routed from one subnet to the other In this case the host transmits the packet to the connecting router s MAC address In the LANplex bridging routing model a packet is bridged as follows see Figure 3 6 The packet enters the LANplex system N HB The packet s destination MAC address is examined by the bridging layer 3 The destination MAC address does not correspond to the MAC address of one of the system ports configured for routing The bridging layer selects a segment port based on the d
147. the session layer PAP relies on NBP to find the addresses of named entities PAP also depends on ATP for sending data The presentation layer maintains information about files formats and translations between formats An AppleTalk internet has two protocols at the presentation layer the AppleTalk Filing Protocol AFP and PostScript AFP provides remote access to files on the network PostScript is a paged description language used by many printers About AARP The AppleTalk Address Resolution Protocol AARP maps the hardware address of an AppleTalk node to an AppleTalk protocol address It does this mapping for both extended and nonextended networks When a node on the network initializes it randomly selects an AppleTalk address for itself At the same time it sends out ten AARP probe packets The probe packets determine whether any other nodes on the network are using the address it has chosen If a node on the network is already using that address the node randomly selects another address and sends out another probe packet About AARP 7 11 The AARP maintains an Address Mapping Table AMT with the most recently used hardware addresses and their corresponding AARP addresses If an address is not in this table AARP sends a request to the protocol address and adds the hardware address to the table when the destination node replies You can view this table called the AARP cache through the LANplex Administration Console 7 12
148. thin 15 hops of the router The table is aged at set intervals as follows After a period of time the RTMP changes the status of an entry from good to suspect After an additional period of time the RTMP changes the status of an entry from suspect to bad After an additional period of time the RTMP changes the status of an entry from bad to really bad Finally the router removes from the table the entry of a nonresponding router with a really bad status The data in the routing table is cross referenced to the Zone Information Table ZIT This table maps networks into zones The section on the session layer protocols includes information about the ZIT Figure 7 3 illustrates a simple AppleTalk network and Table 7 1 shows the corresponding routing table 7 8 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT Network 5 5 Router 802 EE Network 64 64 Router 36 Network 18 20 Interface 2 mI 200 Router 24 Interface 1 interface Network 12 12 Network 103 103 Figure 7 3 A Simple AppleTalk Network Table 7 1 The Routing Table for Router 24 in Figure 7 3 Network Range Distance Interface State 5 5 1 2 Good 12 12 3 3 Good 18 20 2 3 Good 103 103 0 1 Good 64 64 1 3 Good You can view the AppleTalk routing tables in your network through the Administration Console AppleTalk Echo Protocol AEP AppleTalk nodes use the AEP to send datagrams to other nodes in t
149. thod results in fewer spanning trees but it requires dynamic updates to the routing table Nodes that are at the border of the network and have no point beyond them in the RPF spanning tree are called leaf nodes Leaf nodes all receive the first multicast packet If a group member is attached to the leaf node the node continues to accept packets If no group member is attached to the leaf node the node sends back a prune message to the router that sent the packet The message tells the router to send no further packets to this group In the LANplex system the Administration Console IP multicast CacheDisplay includes information about when pruning will occur on the spanning tree Multicast Interfaces DVMRP Metric Value Time To Live TTL Threshold Multicast interfaces on the LANplex system have several characteristics which are described in this section The DVMRP metric value determines the cost of a multicast interface The higher the cost the slower the link The default value is 1 This TTL threshold determines whether the interface will forward multicast packets to other switches and routers in the subnet If the interface TTL is greater than the packet TTL then the interface does not forward the packet The default value is one 1 which means that the interface forwards most packets 5 6 CHAPTER 5 ROUTING WITH IP MULTICAST Rate Limit The rate limit determines how many multicast packets can travel over the inte
150. ting node This response contains all known information regarding all servers of the requested type 6 16 CHAPTER 6 ROUTING WITH IPX About AppleTalk ROUTING IN AN APPLETALK ENVIRONMENT This chapter provides an overview of AppleTalk amp routing and includes these topics AppleTalk Network Elements AppleTalk Protocols About AARP AppleTalk is a suite of protocols defined by Apple Computer Inc for connecting computers peripherals devices and other equipment on a network AppleTalk protocols support most of the functions offered by the Open Standards Interconnect OSI reference model The AppleTalk protocols work together to provide file sharing and printer sharing as well as applications like electronic mail and database access All Macintosh amp computers have AppleTalk connectivity options built into them making it the de facto standard for Apple8 computer networks AppleTalk Network Elements An AppleTalk network consists of different nodes in groups of networks in an AppleTalk internet These nodes can include workstations routers and printers or services for other computers called clients This section describes the elements of an AppleTalk internet AppleTalk networks AppleTalk nodes AppleTalk zones Seed routers 7 2 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT AppleTalk A network in an AppleTalk internet is a cable segment attached to a router Networks AppleTalk Nodes Each ne
151. tion Console enter ip atmArpServer define Enter the number of the ATM port where you want to define the ATM ARP server Enter the IP address of the ATM port you want to define Enter the subnet mask To accept the default value shown in brackets press the Return key at the prompt Example Select ATM port Enter IP address 1 158 101 20 30 255 255 0 0 Enter subnet mask To delete a currently defined ATM ARP server from the top level of the Administration Console enter ip atmArpServer remove The systems prompts you for one or more index numbers associated with the ATM ARP servers that you want to remove The ATM ARP server display shows the index number assigned to each ATM ARP server The system also displays the current index numbers in the prompt Example Select ATM ARP server index es 1 2 all 1 Displaying the ATM ARP Cache Top Level Menu System ethemd fddi display Administering ATM ARP Servers 9 17 To display the contents of the ATM ARP cache from the top level of the Administration Console enter ip atmArpServer arp display atm y i arp defin Ls MatmAmSi removi display b multicast arp remove Ex udpHelper flush ample applet routing p SNMP icmpRouterDiscovery analyze rip is ping IP routing is enabled RIP is active g statistics ICMP router discovery is disabled IP address ATM Address Circuit 158 101 112 2 47 005 80 ffe100 0000 f21a 2130 800
152. tivates redundant links This strategy ensures that all nodes remain connected 5 4 CHAPTER 5 ROUTING WITH IP MULTICAST Reverse Path Forwarding Figure 5 1 shows a simple network with five links gt UJ REN yl Figure 5 1 Simple Network Implemented Without Using Spanning Tree A spanning tree for this network consists of links 1 2 3 and 4 See Figure 5 2 wo g A ml o Oo Figure 5 2 Spanning Tree Algorithm Implemented to Block Redundant Paths Reverse path forwarding RPF is the multicast algorithm in use on the MBONE network RPF is designed to avoid duplicate paths on multi access links It uses a routing table to compute a logical spanning tree for each network source The RPF algorithm has these basic steps When the system receives a multicast packet the algorithm notes the source network of the packet and the interface on the LANplex system that received the packet If the interface belongs to the shortest path towards the source network then the system forwards the packet to all interfaces except the interface on which the packet was received 3 If the condition in Step 2 is false the system drops the packet Pruning Multicast Interfaces 5 5 Pruning is a method used in the RPF algorithm to forward packets to a spanning tree only if group members exist in the tree This me
153. tive bridge forwarding sap i ri i bs Sinn forwarding SAP Received SAP Transmitted SAP dropped appletalk Sap 1064015 22493 0 snmp statistics analyzer script SAP Responses SAP Requests SAP Entries logout 1063532 45 0 SAP GNS Responses SAP GNS Requests 0 438 Table 11 1 describes the IPX SAP statistics Table 11 3 IPX SAP Statistics Field Description SAP Received SAP Transmitted SAP Dropped SAP Responses SAP Requests SAP Entries SAP GNS Responses SAP GNS Requests Number of IPX SAP packets received Number of IPX SAP packets transmitted Number of IPX SAP packets dropped Number of IPX SAP Responses that have been processed Number of IPX SAP Requests that have been processed Number of servers in the server table Number of IPX SAP Get Nearest Service Responses that have been received Number of IPX SAP Get Nearest Service Requests processed Displaying IPX Forwarding Statistics Top Level Menu System ethemet interface fddi Toute summary atm Server rip bridge forwarding sap ip rip M forwarding b ipx enhanced appletalk Sap snmp Mb statistics analyzer script IPX forwarding is enabled RIP is active SAP is active Received 1335653 Hdr Errors 13758 No Routes NetBIOS Rx 150604 Host Rx 1171190 ipx statistics forwarding Example Transmitted 565105 Hop Count Errors 0 Misc Errors 411 NetBIOS Tx 125781 Host Tx 565105 Disp
154. twork Subnet and Host Apply the subnet mask o Result subnet host boundary Y Network l Subnet Host Figure 4 3 How a Subnet Mask Is Applied to the IP Address An example of an IP address that includes network subnet and host parts is 158 101 230 52 with a subnet mask of 255 255 255 0 This address is divided as follows 158 101 is the network part 230 is the subnet part 52 is the host part A router interface is the connection between the router and a subnet In traditional routing models the interface is the same as the port since only one interface can exist per port In the LANplex systems IP routing model more than one port can be connected to the same subnet Each router interface has an IP address and a subnet mask This address defines both the number of the network to which the router interface is attached and its host number on that network A router interfaces IP address serves two functions The IP address is used when sending IP packets to or from the router itself The IP address defines the network and subnet numbers of the segment connected to that interface See Figure 4 4 Routing Table Elements of IP Routing 4 5 Network 2 Network 1 Interfaces 158 101 1 2 Y Y 158 101 2 2 138101271 1 2 1 A Router Interface 1 3 IP Address 158 101 3 2 158 101 3 1 158 101 1 1 A
155. twork is identified by a network number or range of network numbers The network administrator assigns these numbers from a range of valid network numbers Two AppleTalk network numbering systems are currently in use nonextended Phase 1 and extended Phase 2 3Com routers support extended network numbers While the LANplex system will not translate Phase 1 packets to Phase 2 packets it will route packets to a Phase 1 network The LANplex system anticipates that a gateway exists between the two networks to translate the packets An extended network can span a range of logical networks Network numbers in an extended network consist of a range such as 15 through 20 This numbering scheme allows for as many as 16 580 608 nodes although the actual cables will not support this many nodes A node in a AppleTalk network is any addressable device including workstations printers and routers Nodes are physically attached to a network Each AppleTalk node is identified by a unique AppleTalk address that each node selects at initialization The address consists of the node s network number and a unique node number Named Entities When a device on the network provides a service for other users the network administrator can give the device a name The name appears on the Chooser menu of the Macintosh with an associated icon For example the Chooser of the Macintosh can include a printer icon When you select the printer icon several printer name
156. ubnet 157 103 54 0 with subnet mask of 255 255 255 0 IP host interface address 157 103 54 254 with subnet mask of 255 255 255 0 Layer 2 bridging communication is still possible within an IP VLAN or router interface for the group of ports within that IP Interface s IP VLAN IP data destined for a different IP subnet uses the IP routing interface to get to that different subnet even if the destination subnet is on a shared port 2 10 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM VLAN Examples Example 1 Figure 2 1 is an example of a simple configuration that contains three protocol sensitive VLANs 2 IP and 1 IPX that share a high speed FDDI link The end stations and servers are on 10M bps ports with traffic segregated by protocol They are only aggregated over the high speed FDDI link See IP 1 IP 1 IP 2 IP 2 IPX 1 IPX 1 IP 1 ae IPX 1 IP 1 IPX 1 VLAN 1 A VLAN 3 Server Server IP 2 IP 2 VLAN 2 Server Figure 2 1 Example of a Protocol Sensitive VLAN Configuration About VLANs 2 11 Example 2 Figure 2 2 is an example of a configuration that contains two different protocol sensitive VLANs IP and IPX with servers on separate high speed 100BASE T ports The end station clie
157. ulated at regular intervals Static Routes A static route is one you manually configure in the routing table Static routes are useful in environments where no routing protocol is used or where you want to override some of the routes generated with a routing protocol Because static routes do not automatically change in response to network topology changes you should manually configure only a small number of reasonably stable routes Dynamic Routes Using RIP Automated methods of learning routes help you keep up with a changing network environment allowing routes to be reconfigured quickly and reliably Interior Gateway Protocols IGP which operate within intranetworks provide this automated method The LANplex 6 10 CHAPTER 6 ROUTING WITH IPX Service Advertising Protocol system uses RIP one of the most widely used IGPs to dynamically build its routing tables RIP operates in terms of active and passive devices The active devices usually routers broadcast their RIP messages to all devices in a network they update their own routing tables when they receive a RIP message The passive devices usually hosts listen for RIP messages and update their routing tables they do not send RIP messages An active router sends a RIP message every 60 seconds This message contains both the network number for each destination network and the number of hops to reach it In RIP each router that a packet must travel through to reach a destinati
158. us When you gain access to the Administration Console the top level menu appears The Extended Switching software contains top level menus and additions to the Bridge and IP menu options not available with Intelligent Switching software Option Descriptions Menu options System Administer system level functions ethernet Administer Ethernet ports Menu options vary fddi Administer FDDI resources by level of access ATM Administer ATM resources bridge Administer bridging VLANs ip Administer IP ipx Administer IPX appletalk Administer Appletalk snmp Administer SNMP analyzer Administer Roving Analysis script Run a script of console commands logout Logout of the Administration Console Type for help Select a menu option The following sections show the enhanced menus provided with Extended Switching software All other menu items appear in the LANplex 2500 Administration Console User Guide p The RMON feature is available through SNMP only This feature is not available through the Administration Console See Chapter 13 Remote Monitoring RMON Technology for more information about this feature Using Menus 1 3 Bridge Menu From the bridge menu you can view information about and configure Ethernet LANs including VLANs Figure 1 1 shows the bridge menu Top Level Menu bridge menu interface menu System display summary ethemet mode detail fddi ipFragmentation define
159. use SAP routers typically do not act as servers and require no Service Type assignment 4 Server Name This field contains the 48 byte character string name that is assigned to a server The server name in combination with the service type uniquely identifies a server on an internetwork Network Address This 4 byte field contains the server s network address Node Address This 6 byte field contains the server s node address Socket Address This 2 byte field contains the socket number that the server uses to receive service requests 4 Hops to Server This 2 byte field indicates the number of intermediate networks that must be passed through to reach the server associated with this field entry Each time the packet passes through an intermediate network the field is incremented by 1 By using SAP servers can advertise their services and addresses The information that these servers broadcast is not directly used by clients rather it is collected by a SAP agent within each router on the server s segment The SAP agents store this information in a server information table If the agents reside within a server the information is also stored in their server s bindery The clients can then contact the nearest router or file server SAP agent for server information Server Table Interface Name The Elements of IPX Routing 6 13 The SAP broadcasts that servers and routers send are local and therefore only re
160. uter pod Ww t Routing Layer y 9 2 3 Router Interfaces i i T i i i i fi i E RUE i Bridge o Y 5 d Bridging Layer A pi l i j 2 3i Subnets l i i i I Y we Transmitting Host Destination Host Figure 3 7 Routing in the LANplex Bridging and Routing Model 3 8 CHAPTER 3 BRIDGING AND ROUTING IN THE LANPLEX 9SYSTEM eec e ee e eoc ROUTING WITH IP TECHNOLOGY This chapter gives an overview of IP routing technology specifically defining What IP routing involves What elements are necessary for IP routers to effectively transmit packets How IP routing transmission errors are detected and resolved Routing with classical IP over ATM IP Routing and the OSI Model An IP router unlike a bridge operates at the network layer of the OSI Reference Model That is it routes packets by examining the network layer address IP address Bridges use the data link layer MAC addresses to make forwarding decisions See Figure 4 1 OSI Reference Model Figure 4 1 OSI Reference Model and IP Routing 4 2 CHAPTER 4 ROUTING WITH IP TECHNOLOGY When an IP router sends a packet it does not know the complete path to a destination only the next hop Each hop involves three steps The IP routing algorithm computes the next hop IP address and next router interface using the routing table entries The A
161. uters Tics An estimate of how long it will take the packet to reach this segment A tic is approximately 55 milliseconds Node The 6 byte address of the router that can forward packets to the segment A node address of all zeroes 00 00 00 00 00 00 means that the route is connected directly to the router Age The number of seconds that have elapsed since the last time the route was heard from 11 6 CHAPTER 11 ADMINISTERING IPX ROUTING Displaying the Routing Table Top Level Menu You can display the routing tables for the system to determine which routes are configured and if they are operational To display the contents of the routing table from the Administration Console top level menu enter ipx route display System ethemet bs fas re The example displays the configuration of IPX forwarding RIP and SAP static bridge forwardi remove as well as the routing table ip rip flush Dipx enhancea w us IPX forwarding is enabled RIP is active SAP is active l e Interface Address Hops Tics Node Age logout 2 45469f02 5 6 08 00 02 04 80 b6 44 2 c2c028ca 4 28 08 00 02 04 80 D6 85 2 aaaaaaaa 6 671 08 00 02 04 80 b6 85 Defining a Static Route Top Level Menu System ethemet interface fddi P route display atm server i static bridge forwarding remove ip rip flush D ipx enhanced appletalk sap snmp statistics analyzer script logout Before you define static routes o
162. ved inExReplies Number of ZIP extended replies received inGniRequests inGniReplies inLocalZones inZoneLists inObsoletes inZoneCons inZonelnvs inErrors outQueries outReplies outExReplies outGniRequests Number of ZIP GetNetInfo request packets received Number of ZIP GetNetInfo reply packets received Number of Zip GetLocalZones requests packets received Number of Zip GetZoneLists requests packets received Number of ZIP Takedown or ZIP Bringup packets received Number of times a conflict has been detected between this entity s zone information and another entity s zone information Number of times this entity has received a ZIP GetNetinfo reply with the zone invalid bit set because the corresponding GetNetinfo request had an invalid zone name Number of ZIP packets received that were rejected for any error Number of ZIP queries sent Number of ZIP replies sent Number of ZIP extended replies sent Number of ZIP GetNetInfo packets sent continued Displaying NBP Information Top Level Menu System ethemet interface fddi route ddp atm aarp rtmp bridge zone zip ip forwarding p nbp p M appletalk ping snmp My statistics analyzer script logout Viewing Appletalk Statistics 12 17 Table 12 3 ZIP Statistics continued Field Description outGniReplies Number of ZIP GetNetinfo reply packets sent out of this port outzonelnvs Number of times this entity has sent a ZIP GetNetInfo reply with the z
163. w the zone information table by network number or network zone ZIP creates a zone information table in each router Each entry in the ZIT is a tuple or pair that includes a network number and a network zone name When an NBP packet arrives at the router it includes the zone name which the router compares with entries in the zone table The router then matches the network number from the matching ZIT tuple to the one in the RTMP table to find the interface where it can route the packets 7 10 CHAPTER 7 ROUTING IN AN APPLETALK ENVIRONMENT Presentation Layer AppleTalk Data Stream Protocol ADSP The ADSP works with the ATP to ensure reliable data transmission Unlike ATP however ADSP provides full duplex byte stream delivery This means that two nodes can communicate simultaneously ASDP also includes flow control so that a fast sender does not overwhelm a slow receiver AppleTalk Session Protocol ASP The ASP passes commands between a workstation and a server once a connection is made between the two ASP ensures that the commands are delivered in the same order as they were sent and returns the results of these commands to the workstation Printer Access Protocol PAP The PAP maintains communications between a workstation and a printer or print service The PAP functions include setting up and maintaining a connection transferring the data and tearing down the connection on completion of the job Like other protocols at
164. warding ipx checksum The entry is removed M appletalk ping snmp statistics analyzer script logout Flushing All Cache To flush all AARP cache entries Entries Top Level Menu system 1 At the Administration Console s top level menu enter ethernet interface fddi route display appletalk aarp flush atm b aarp remove bridge zone p flush ip forwarding ipx checksum appletalk ping snmp statistics analyzer script logout 12 10 CHAPTER 12 ADMINISTERING APPLETALK ROUTING Displaying the AppleTalk allows for the logical grouping of nodes into zones to make Zone Table navigation through the network easier This is done with the Zone Top Level Menu system ethernet fddi atm ipx b appletalk snmp analyzer script logout interface route aarp Dzone forwarding checksum ping statistics b network b zone Information Protocol ZIP ZIP helps routers maintain a mapping of network numbers to zones in the entire network To do this ZIP creates and maintains a Zone Information Table ZIT in each router The entries in this table match the network numbers with the zone names In the Administration Console you can display the zone table either by network numbers or by zones To display the zone table From the Administration Console top level menu enter appletalk zone display network OR appletalk zone display zone Configuring Forwarding Top Level Menu Sys
165. warding the system discards any IPX packets not addressed directly to one of its defined IPX interfaces IPX forwarding default By default IPX forwarding is disabled Top Level Menu To enable or disable IPX forwarding RM errem 1 From the Administration Console top level menu enter fddi ti ain ae ipx forwarding bridge forwarding bi enhanced 2 Enter the IPX forwarding state enabled Or disabled To use the value in sa brackets press Return at the prompt analyzer script logout Setting the RIP You can select a RIP mode that is appropriate for your network RIP can Mode operate in any of three modes m Off The system ignores all incoming RIP packets and does not generate any RIP packets of its own m Passive The system processes all incoming RIP packets but does not broadcast periodic or triggered RIP updates or respond to RIP requests m Active The system processes all incoming RIP packets responds to explicit requests for routing information and broadcasts periodic and triggered RIP updates 11 12 CHAPTER 11 ADMINISTERING IPX ROUTING RIP default mode Top Level Menu interface Toute Server By default RIP is off To set the RIP operating mode From the Administration Console top level menu enter ipx rip Enter the RIP mode off passive Of active To use the value in bridge forwarding in rip brackets press Return at the prompt M ipx enhanced appletalk Sap
166. without a specific description of that device 3Com ships SNMP MIB files with LANplex Extended Switching System software as ASN 1 files The data in the MIB consists of objects that represent features of the equipment that an agent can control and manage Examples of objects in the MIB include a port that you can enable or disable and a counter that you can read A counter is a common type of MIB object used by RMON A counter object might record the number of frames transmitted onto the network The MIB might contain an entry for the counter object something like the one in Figure 13 2 for the counter object Management Information Base MIB 13 5 etherStatsPkts OBJECT TYPE SYNTAX Counter ACCESS read only STATUS mandatory DESCRIPTION This is a total number of packets received including bad packets broadcast packets and multicast packets i etherStatsEntry 5 Figure 13 2 Example of an RMON MIB Counter Object The displayed information includes these items The formal name of the counter is etherStatsPkts Ethernet Statistics Packets The access is read only The number of the counter s column in the table 5 The name of the table in which the counter resides is 3CometherStatTable although this does not appear in the display You do not need to know the contents of every MIB object to manage a network Most network management applications including Transcend Enterprise Manager Software make the MIB transparent
167. ws the Appletalk menu For example to define a new AppleTalk interface you would enter appletalk at the top level menu interface at the AppleTalk menu then define at the interface menu Top Level Menu System ethernet fddi atm bridge Ip ipx appletalk snmp analyzer script logout Figure 1 4 appletalk menu zone forwarding checksum ping Mb statistics interface menu display define remove route menu display flush aarp menu display remove flush statistics menu p rtmp Appletalk Menu Hierarchy zip nbp e t te e t e VLANS ON THE LANPLEX SYSTEM This chapter contains A description of Virtual LAN VLAN concepts and their operational aspects in the LANplex 2500 system Examples of VLAN configurations About VLANs Types of VLANs The VLAN concept in LAN technology helps minimize broadcast and multicast traffic It also makes end station moves adds and changes easier for the network administrator In the LANplex system VLANs allow you to Create independent broadcast domains to optimize network performance and create firewalls Form flexible user groups independent of the users physical network location You can use several types of VLANs to group users These types include Port group VLANs MAC address group VLANs Application oriented VLANs Protocol sensitive VLANs Port Group VLANs Port group VLANs group togeth
168. y remove addAdvertisement removeAdvertisement addPvc removePvc 2 Administering interfaces 9 7 You might want to change the configuration of an interface you have already defined You can add one or more advertisement addresses or PVCs to an interface through the aadadvertisement and aaaevc commands as well as through the IP interface modify command If you add or change an advertisement address or PVC through the modify command you must re enter all addresses or PVCs associated with the interface not just the one you want to add or change To modify an IP interface From the top level of the Administration Console enter ip interface modify You are prompted for the interface parameters Press Return at the prompts for the parameters you do not want to modify Modify the existing interface parameters by entering a new value at the prompt You might want to remove an interface if you no longer route on the ports associated with the interface To remove an IP interface definition From the top level of the Administration Console enter ip interface remove Enter the index numbers of the interfaces you want to remove If you have defined one or more PVCs on the interface the Administration Console displays a message indicating that the PVCs will be removed with the interface The following is an example of a prompt for interface 2 which has one PVC associated with it 1 PVC associated with the interface i
169. ystem but the frame s source port is not a member of the VLAN definition then the frame is flooded according to the default VLAN assigned to that port If the protocol type of the received frame has no VLAN defined for it in the system the frame is flooded to the Default VLAN for the receive port 2 6 CHAPTER 2 VLANS ON THE LANPLEX SYSTEM VLAN Exception Flooding This example shows how flooding decisions are made according to VLANs set up by protocol assuming an 18 port switch Index VLAN Ports 1 Default 1 18 2 IP 1 12 3 IPX 11 16 Data received on Is flooded on Because IP port 1 VLAN 2 IP data received matches IP VLAN on the source port IPX port 11 VLAN 3 IPX data received matches IPX VLAN on the source port XNS port 1 VLAN 1 XNS data received matches no protocol VLAN so the Default VLAN is used If data arrives on a switch port for a certain protocol and VLANs for that protocol are defined in the system but not on that switch port the default VLAN defines the flooding domain for that data This case is called VLAN exception flooding This example shows how the VLAN exception flooding decision is made assuming an 18 port switch Index VLAN Ports 1 Default 1 18 2 IP 1 10 Overlapped IP VLANs About VLANs 2 7 Data received on Is flooded on Because XNS port 1 VLAN 1 XNS data does not match any defined VLAN in the system IP port 2 VLAN 2 IP data received matches IP VLAN 2

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