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Disk Array Controller Configuration Utilities Installation Guide and

1. ccessscecseseeeeseeeseenceseseeeeensesenseenenenenes 2 8 SCSI Transfer Parameters eee eeeeeeee een 2 11 Startup Parameters o eee eee eee eee eee ee een ete 2 12 Low Level Formatting the Drives eee 2 14 Automatic Configuration sese 2 17 Manual Configuration essen 2 21 Defining and Creating Drive Groups wu 2 21 Defining and Creating a System Drive ee 2 26 Saving the New Configuration sese 2 29 Initializing the System Drives u eee 2 30 Exiting DAGGE is E ei E St Shee EL 2 33 Navigating within DACCF u eee eee eee ent 2 33 DACCF Screen Regions and Objects 2 33 Getting Around Within DACCF eee 2 34 Chapter 3 Administering the Array eu Mc Hd 3 1 Viewing and Updating the Existing Configuration 3 1 Changing the Existing Write Policy eee 3 2 Creating New Standby Drives ssseseeeee 3 3 Creating New Drive Groups and System Drives 3 4 Expanding the Capacity of a Drive Group z eee 3 4 Saving the Updated Configuration to Memory 3 6 Manual No 771953 V Rebuilding Driye Seriana and a 3 7 Running a Consistency Check sse 3 9 Using Options on the Tools Menu eee 3 11 Viewing the Bad Block Table eee 3 11 Viewing Device Error Counts seeeeeene 3 13 Backup Restore Configuration 3 1
2. Select NO to abort the process and return to the Initialize System Drive screen An initialization status screen will be displayed with the initialization progress of each drive included in the operation Note The initialization rate for a given system drive is dependent upon the size of the drive and the RAID level specified for the drive Therefore some system drives will initialize more quickly than others AN Caution Do not interrupt the initialization process or you will have to restart and complete a full initialization before using the drive 6 Atthe conclusion of the initialization a completion message is displayed Press any key to return to the Main menu Preparation of the array is complete at this point You can exit DACCF at this time and proceed to load the operating system onto the array 2 32 DACCF User s Manual Preparing the Array Exiting DACCF To exit DACCE follow these steps 1 Get to the Main menu 2 Press the Esc key The Exit confirmation box will appear Select YES to exit DACCF and return to the MS DOS command prompt DOS based version or reboot the system BIOS version Select NO to remain in DACCE Navigating within DACCF DACCF Screen Regions and Objects You control DACCF via a text based interface Screen areas and objects that you ll encounter while using DACCF are shown in Figure 2 28 and explained below MYLEX Disk Array Controller Configuration Utilit
3. Data transfer rate MHz 246 MHz Command tagging Enabled SCSI data bus width 16 Bit Figure 2 7 SCSI Transfer Parameters Menu To change a SCSI transfer parameter do the following 1 Highlight the desired parameter using the cursor keys 2 Press the Enter key to change the value 3 When the correct value is displayed either Repeat steps 1 amp 2 above but for a different parameter or Press the Esc key to return to the Edit View Parameters menu The change will be retained Data Transfer Rate MHz The SCSI Transfer function sets the maximum transfer rate for each drive channel The default setting is 20MHz This setting produces 20 MB sec transfers for Fast SCSI and 40 MB sec transfers for Wide and Ultra SCSI In general it is not necessary to change this parameter since the controller negotiates the supported transfer rate with all of the drives Manual No 771953 2 11 Setting Controller Parameters for Your Application Note Problems communicating with a drive can be caused by several conditions e g improper termination wrong drive ID setting SCSI cable is too long faulty equipment etc Command Tagging Command tagging controls SCSI command tag queuing support for each drive channel This allows drives to work on multiple commands at the same time This function normally remains enabled Disable only when using older SCSI drives not supporting command tag queuing SCSI Data Bus Width
4. After making changes to write policy on existing system drives or creating new system drives the configuration must be saved to the controller s memory To save the configuration 1 From the System Drive Definition menu press the Esc key twice 2 Aconfirmation dialog box will be displayed Select YES in the dialog box to save the configuration and you will return to the Main menu Select NO to discard all changes made to drive groups group arrangements system drives and write policy and you will return to the Main menu or Press the Esc key to cancel the save process and return to the System Drive Definition menu Any changes are retained and additional modifications can be made However the configuration will need to be saved before proceeding to the last step of array preparation 3 6 DACCF User s Manual Administering the Array Rebuilding Drives If one of the physical drives fails suddenly in an array with redundant system drives RAID level 1 3 5 or 1 0 and no standby drives the DAC system will continue to function without any interruption However during this critical period the DAC system can tolerate no further physical drive failures as data on the drives is no longer redundant During this period the array is considered to be in a Critical state In order to restore the system s redundancy fault tolerance the failed physical drive needs to be replaced with a functional physical drive of the s
5. The Force 8 bit Drive Channel function allows the controller to communicate with Wide SCSI 16 bit devices connected to it through a Narrow SCSI 8 bit data cable on the specified drive channel In general it is not necessary to change this parameter since the controller negotiates the supported data bus width Startup Parameters Device startup parameters affect the power consumption of the disk devices within the array A running drive consumes a fraction of the power necessary to start the drive To minimize the strain on the power supply of the array the drives can be started in sequence spreading the consumption of power out over a defined period of time To change any device startup parameter below select Startup Parameters from the Edit View Parameters menu The Start up Parameters menu appears Figure 2 8 Start up Farameters Spin up option Automatic Number of devices per spin 2 Delay seconds 6 Figure 2 8 Start Up Parameters Menu To change a parameter do the following 1 Highlight the desired parameter using the cursor keys 2 12 DACCF User s Manual Preparing the Array 2 Press the Enter key to change the value 3 When the correct value is displayed either Repeat steps 1 amp 2 above but for a different parameter or Press the Esc key to return to the Advanced Functions menu The change will be retained Spin Up Option The Spin up function controls how the S
6. n Channel nn Target DACO6HXX in Firmware n nn n n Pak Drys Size MB System Drive Definition n 3 3839 1 Create System Drive Z Toggle Write Folicu System Drivelt n Raid Level Capacitu 5 Sus Dry Size MB RAID Write Mode 2626 MB Do you want to Create this System drive 7 NO NEED NEN Figure 2 23 System Drive Summary Select YES to create the system drive and add it to the System Drive Table The drive is added to the table and control is returned to the System Drive Definition menu Select NO to cancel the creation of the system drive and return to the System Drive Definition menu 6 Repeat steps 2 through 6 to create additional system drives 2 28 DACCF User s Manual Preparing the Array Note Several arranged groups packs can be included in a single system drive if each of the arranged groups has the same number of drives This is known as spanning a system drive across drive groups and is automatically configured when the size of the system drive is entered Note that you will not be able to use the Add Drive to Last Pack function on a pack which contains a spanned system drive Toggle Write Policy To change write policy of any system drive use the following procedure 1 Select Toggle Write Policy from the System Drive Definition menu The cursor will move to the System Drive Table 2 Use
7. standby replacement table reboot the system from a DOS bootable floppy run the configuration utility and select the option view update configuration from the main menu A red box labeled Drive Remap List will be displayed Selecting the box will allow you to continue You should save the configuration without making any changes and exit the configuration utility This will clear the replacement table You may now proceed to boot your system and continue normal operations In normal use the replacement table limit of 8 should not cause any problems Assuming that a disk fails about once a year drives we support generally come with a 5 year warranty the system would run continuously Manual No 771953 Glossary 9 Glossary for a minimum of 8 years before the table would need to be cleared Stripe Order The order in which SCSI disk drives appear within a drive group This order must be maintained and is critical to the controller s ability to Rebuild failed drives Stripe Size The stripe size is defined as the size in kilobytes 1024 bytes of a single I O operation stripe of data data residing in actual physical disk sectors which are logically ordered first to last is divided over all disks in the drive group Stripe Width The number of striped SCSI drives within a drive group Striping Refers to the storing of a sequential block of incoming data across multiple SCSI drives in a group For
8. 64K 64K firmware 2 6 8K 16K 32K SCSI Transfer Parameters Data transfer rate MHz 20MHz Asynch 5MHz 10MHz Command tagging Enabled Disabled only for old drives SCSI data bus width 16 bit 8 bit Startup Parameters Spin up option Automatic On Power Number of devices per spin 2 1 3 4 5 6 7 8 Delay seconds 6 12 18 24 30 a supported only in early firmware versions To facilitate tuning of the array for optimal performance a number of controller settings as opposed to the array configuration stored in the controller s memory can be changed These controller settings or parameters are accessed by selecting the Advanced Functions option on the Main menu Figure 2 3 2 4 DACCF User s Manual Preparing the Array MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX tin Firmuare n nn n n Main Menu Bi Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild H5 Initialize System Drive 46 Consistency Check B7 Tools B8 Select DACI64 49 Advanced Functions Choose this option to view or edit controller configuration parameters Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 2 3 Advanced Functions Option When selected the Edit View Parameters menu appears Figure 2 4 MYLEX Disk Arr
9. The timeout condition also applies to drives that hold the SCSI bus for a long period Media Error Recovery Flow If a drive reports a media error on a read command the controller reconstructs the data from the mirror or from parity and data on other drives It then writes the data to a different area of the disk to clean the error if possible The data is read from the new location for verification If the read of the data at the new location fails the controller issues a reassign to the drive selecting another new location and then repeats the write verify operation A reassign failure or two successive failures in verification will result in the drive being killed Manual No 771953 D 3 Errors Which Cause a Drive to be Killed Interrogation Sequence Start Drive During the drive startup sequence the controller issues several SCSI commands Inquiry TUR Sync negotiation and when supported Wide negotiation Following these commands the controller issues a read command on a reserved block of the drive The timeout for all of these commands is three seconds If any error including timeout is encountered during the interrogation sequence the drive is killed The interrogation sequence is performed for each drive every time an error occurs on the bus which requires a SCSI Reset Operator Command A drive can also be killed via DACCF or via a Mylex utility for a specific operating system D 4 DACCF User s
10. 3 Iz od 5 G 3 Intelligent Battery Backup Unit een G 3 Logical Drive States reete bae is G 4 Online A Logical Drive is in an online state if G 4 Critical A Logical Drive is in a critical state if G 4 Offline A Logical Drive is in an offline state if G 4 Logical Drives tero ipe en etra tea teense G 5 MIEFOTITQ eroe dos nea cea e toi ri eene ee t e re E terre G 5 Pack isnnAntuneBenegne penu Hee ate n N G 5 acum G 5 RAID ac e bl e e e eee ete ve ge an e s eee G 5 RAID Levels 5 atrae eet tpfe sk G 5 Replacement Table ccceccsccsesceceeeceeeseceeeseneeenseeeeeseeeseseeeseneeenens G 6 Rotated XOR Redundancy ee eee eee eee eee G 6 SGSI Drive eam ee RU e erint G 7 SGSI Drive States cee coca et Re eR G 7 Ready A SCSI disk drive is in a ready state if it G 7 Online A SCSI disk drive is in an online state if it G 7 Standby A SCSI disk drive is in a standby state if it G 7 Dead A SCSI disk drive is in a dead state if it G 7 Rebuild A SCSI disk drive is in a rebuild state G 8 Segment Size sns tra decade reine po Y ene ge ev das G 8 Ie I M G 8 Standard Disk Drive essesssssesesseee
11. 4 Add Capacity Warning Message Select YES to begin capacity expansion on the target pack Select NO to cancel the capacity expansion process and return to the previous menu AN Caution Once the Add Drive to Last Pack process has started it cannot be interrupted by user intervention You must allow the process to reach completion 6 If you chose to proceed with expansion the Add Capacity status screen appears showing the progress of data migration restriping across the target pack Manual No 771953 3 5 Viewing and Updating the Existing Configuration 7 Atthe conclusion of the data migration a message indicating successful completion will be displayed Press any key to return to the View Update Configuration menu Note If a drive becomes dead during the capacity expansion and a standby drive is available a rebuild operation on the standby will occur after the capacity expansion completes in critical mode A message indicating success will be displayed If the capacity expansion was performed on a RAID 1 system drive the RAID level after data migration will be RAID 0 1 Mylex RAID 6 Your next tasks will be to define one or more system drives for the new available capacity then to initialize those system drives Follow the instructions presented in Defining and Creating a System Drive and Initializing the System Drives in the previous chapter Saving the Updated Configuration to Memory
12. Manual Glossary BBU See Battery Backup Unit Bad Block Table or Bad Data Table There are two bad block tables that the controller automatically maintains The Rebuild Bad Block Table stores information on bad blocks encountered during a rebuild or consistency check process The Write Back Bad Block Table stores information on all irrecoverable write back errors that occur DACCE provides commands that allow you to see either of these two tables Battery Backup Unit A Battery Backup Unit is an add on module that provides power to a Mylex Disk Array Controller cache memory in the event of a power failure The battery backup module monitors the write back cache on the controller and provides power to the cache if it contains data not yet written to the drives when power is lost Cache Controller memory used to speed up data transfer to and from a disk Cache Flush Refers to an operation where all unwritten blocks in a Write Back Cache are written to the target disk This operation is necessary before powering down the system Cache Line Size See Segment Size Manual No 771953 Glossary 1 Glossary Channel Refers to one SCSI bus on a Mylex Disk Array Controller Each controller provides at least one channel or additional channels with optional upgrades Consistency Check Refers to a process where the integrity of redundant data is verified For example a consistency check of a mirrored drive wil
13. Refers to a SCSI drive s current operational status At any given time a SCSI drive can be in one of five states READY ONLINE STANDBY DEAD or REBUILD The controller stores the state of the attached SCSI drives in its non volatile memory This information is retained even after power off Hence if a SCSI disk is labeled DEAD in one session it will stay in the DEAD state until a change is made either by using a system level utility or after a rebuild Each of the states is described below Ready A SCSI disk drive is in a ready state if it Is powered on and Is available to be configured during the current session but remains unconfigured Online A SCSI disk drive is in an online state if it Is powered on and Has been defined as a member of a drive group and Is operating properly Standby A SCSI disk drive is in a standby state if it Is powered on and Is able to operate properly and Was NOT defined as part of any drive group Dead A SCSI disk drive is in a dead state if it Is not present or Manual No 771953 Glossary 7 Glossary If it is present but not powered on or If it failed to operate properly and was killed by the controller When the controller detects a failure on a disk it kills that disk by changing its state to dead A SCSI drive in a dead state does not participate in any I O activity No commands are issued to dead drives Rebuild A SCSI disk dri
14. Saving updated configuration 3 6 SBY 3 5 SCSI transfer parameters 2 11 command tagging 2 12 data transfer rate 2 11 SCSI data bus width 2 12 Selecting a controller 2 2 Soft errors 3 13 spanned drive 3 4 Standby drives creating 3 3 Starting DACCF BIOS version 1 2 DOS version 1 2 stripe width 2 27 System drive defining and creating 2 26 System drives creating new 3 4 initializing 2 30 toggle write policy 2 29 T Tools bad block table 3 11 error counts for a device 3 13 Tools menu 2 14 U Using Options on the Tools Menu 3 11 V View Rebuild BBT 3 12 View Write Back BBT 3 12 Viewing updating the configuration 3 1 Ww R Write back caching 2 19 RDY 3 5 write policy 2 29 Index 2 DACCF User s Manual
15. accurate and Mylex recommends that you check that source first 3 Review the configuration from the selected source and decide if this source should be saved to both sources To save the configuration Press the S key To not save the configuration and to review the other source for a more accurate copy of the configuration follow the directions on the screen Installation Abort An Installation Abort message may appear when the configuration information stored in the controller s memory doesn t agree with the state of the drives as reported by controller BIOS during power up To fix this condition Ensure that all devices are connected powered on and functioning properly 2 Reboot the computer system If the problem persists do the following 1 Rerun DACCF Manual No 771953 D 1 Configuration Checksum Error 3 4 When the error message is displayed press any key A summary of the state of the devices will be displayed To save the setup press the S key The configuration will be saved and you ll be returned to the Main menu To abort the automatic configuration process press the Esc key At this point you will need to turn off power to the array and to the computer and either resolve the hardware problem by adding or removing disk drives as necessary or decide to perform a manual configuration The computer and array must then be powered on and DACCF rerun Power cycle the array and th
16. and storage device hardware must already be properly installed and connected before running the DACCF utilities How you start DACCF depends on whether you will be running the DOS based or BIOS resident version Manual No 771953 1 1 Starting DACCF Installing and Starting the DOS Version of DACCF You will run DACCF from a floppy diskette We recommend you make a DOS bootable copy of the DACCF Configuration amp Utilities diskette and run the program from this diskette 1 Create a DOS bootable floppy diskette 2 Copy DACCF EXE and DACD EXE from the DACCFG directory on the original DACCF Configuration amp Utilities diskette to the bootable floppy diskette 3 Start the system using the bootable floppy diskette you just created 4 Atthe DOS prompt type A XDACCF lt arg gt lt where arg is an optional command line argument Appendix C contains an explanation of the most useful command line arguments which can be supplied DACCF will locate the Mylex Disk Array Controllers and scan the SCSI device chains attached to it If the utility finds more than one controller you will be prompted to select a controller When the DACCF Main menu appears the utility software is up and running Next you will either set controller parameters in the utility or move directly to preparing your array Chapter 2 Starting the BIOS Version of DACCF During system power up the BIOS displays a sign on message with its vers
17. by other means and used in a restoration unpredictable behavior will result 3 16 DACCF User s Manual Administering the Array Clearing the Configuration Use the Clear Configuration option to erase an existing controller configuration from memory and disks for firmware version 3 x and above AI drive groups system drives and RATD levels will be cleared Any controller settings hardware parameters will remain unchanged WARNING Any data on system drives will be lost when the configuration is cleared and a new configuration is created Use this option with extreme caution and ensure that you have made a backup of the configuration before clearing the configuration To clear a configuration follow these steps 1 Select Clear Configuration from the Tools menu A Clear Configuration confirmation will be displayed Select YES to clear the current configuration You will return to the Tools menu Select NO to abort the clearing of the configuration You will also return to the Tools menu 8 Note All Mylex Disk Array Controllers are shipped with the configuration cleared Printing the Configuration To create a printable copy of the configuration stored in a text file which can be printed and used to configure the array manually follow these steps 1 Select Print Configuration from the Tools menu An output file name box will appear 2 Input the name of the file and press the Enter key The filename
18. can be up to 30 characters including the drive prefix and pathname Mylex suggests that you name the file so that you can easily recognize it when you need it for example RAID TXT or ARRAY TXT 3 Aconfirmation box will appear Manual No 771953 3 17 Using Options on the Tools Menu Select YES to create the configuration text file The system will pause briefly while the configuration file is written A message at the bottom of the screen will display indicating successful creation of the file The resulting file will be written in ASCII text format which can be viewed or printed with a word processor or text editor To return to the Tools menu press any key Select NO to abort the creation of the configuration description file You will return to the Tools menu Mylex recommends that a printed copy of the output along with a diskette containing both the file that created the printed copy and a copy of the configuration file created with the Backup Configuration utility be kept in a safe place While the output report is largely self explanatory a few items are worth noting In the section of the configuration report entitled Physical Pack Information a line reading Pack 0 1 0 1 1 1 2 Indicates that three physical drives are part of the first drive group in the array These physical drives are all located on controller channel 1 and have SCSI ID s of 0 1 and 2 respectively Furthermore the
19. ddfc This sets a bitto disable a disconnect on first command by any device on the SCSI bus This switch is available to fix a problem seen in some devices that try to negotiate on a reconnect a function which is not supported by the DAC Seagate Hawk drives with some firmware levels some Seagate Barracuda drives and some older IBM drives are known to attempt to do this If a drive is not seen on power up but can be accessed after a warm boot this could be the problem If you see a drive go off line for no apparent reason this could also be the problem To remedy this situation run DACCF DDFC Once the main menu is displayed you can then exit the utility The bit will be set edfc This resets the bit to allow disconnects on first command Manual No 771953 C 1 C2 DACCF User s Manual Appendix D DACCF Error Conditions NVRAM Flash Configuration Mismatch The controller stores two copies of the array configuration in different memories of the controller One copy is stored in Non volatile RAM the other in an Electrically Eraseable Read Only Memory or Flash EEPROM During initialization DACCF compares each copy of the configuration If a difference is detected the error message above is displayed To remedy this problem 1 Press any key The Load Configuration screen will display 2 Select the source to view either NVRAM or FLASH memory In most cases the information stored in FLASH memory will be more
20. example if there are 3 SCSI drives in a group the data will be separated into blocks and block 0 of the data will be stored on SCSI drive 0 block 1 on SCSI drive 1 block 2 on SCSI drive 2 block 3 on SCSI drive 0 block 4 on SCSI drive 1 and so on This storage method increases the disk system throughput by ensuring a balanced load among all drives System Drives A system drive is equivalent to a logical drive System drives are presented to the operating system as available disk drives each with a capacity specified by the Mylex Disk Array Controller Target ID A target ID is the SCSI ID of a device attached to a Mylex Disk Array Controller Under firmware versions below 2 6 each SCSI channel can have up to 7 attached SCSI devices target ID from 0 to 6 Under firmware Glossary 10 DACCF User s Manual Glossary versions at or above 2 6 each SCSI channel can have up to 15 attached SCSI devices target ID from 0 to 6 and 8 to 15 Write Back Cache Refers to a caching strategy whereby write operations result in a completion signal being sent to the host operating system as soon as the cache not the disk drive receives the data to be written The target SCSI drive will receive the data at a more appropriate time in order to increase controller performance An optional cache battery backup or an Uninterrupted Power Supply UPS can be used to protect against data loss as a result of a power failure or system crash Wri
21. new controller from the information contained on the drives In most cases manual backup restore should not be used USERS OF DAC FIRMWARE VERSION 2 6 OR BELOW are advised to perform manual backup and restore as described below 3 14 DACCF User s Manual Administering the Array To backup or restore a configuration do the following 1 Select Backup Restore conf from the Tools menu 2 Amessage warning you to exercise caution when using this utility will appear Press any key to continue 3 The Backup Restore Conf Configuration menu appears Figure 3 13 Backup Restore Conf Backup Conf iguration Restore Configuration Figure 3 13 Backup Restore Conf Menu Backup Configuration 1 Select the Backup Configuration option to back up the current controller configuration to a file on a floppy disk WARNING Configuration Backup must be made only onto a blank preformatted floppy disk or data corruption of the configuration information can occur 2 You ll be prompted to specify the name and location of the backup file The filename can be up to 30 characters including the floppy drive prefix and pathname Mylex suggests that you name the file so that you can easily recognize it when you need it for example RAID CNF or ARRAY CNE 3 Enter the name of the file and press the Enter key A confirmation box will appear Select YES to proceed with backup of the configuration The configuration wil
22. the write policy follow these steps 1 Select View Update Configuration from the Main menu 2 Select Define System Drives from the View Update Configuration menu Manual No 771953 B 3 3 Select Toggle Write Policy from the System Drive Definition menu 4 Highlight the desired system drive using a mouse or the cursor keys and press the Enter key to change the write policy for that drive 5 Repeat step 4 for other system drives 6 When finished press the Esc key twice and answer YES when prompted to save the configuration Do I need to initialize the system drive again after changing the controller cache write policy No Initialization of the system drive will erase any data that is stored on it When I make a new drive on line all my data is corrupted When should I use the Make On line option The Make On line option should only be used in an emergency situation when data has to be recovered from a disk array It can be used if a fault tolerant array is running in a critical state that is a drive has failed and the array is reading and writing using mirror or parity information and another drive failure occurs At this point the array has lost the ability to store data The Make On line option forces the drive on line so that the information can be copied to another medium Use the Rebuild function to reconstruct data on a new drive that has just replaced a failed drive Why do I need to copy D
23. 4 Clearing the Configuration eee 3 17 Printing the Configuration seem 3 17 Appendix A DACCF File List PCI RAID DAC Products werent A 1 Appendix B Frequently Asked Questions Appendix C Command Line Arguments Appendix D DACCF Error Conditions NVRAM Flash Configuration Mismatch sees D 1 Installation ABON suisse toe eden tte ree tenete ze D 1 Configuration Checksum Error ssssseeee D 2 Errors Which Cause a Drive to be Killed D 2 SCSI Sequence Error sse D 3 SCSI Busy StU S aa 2 0g ie ashes pine D 3 Timeout on a Command eee eee D 3 Media Error Recovery Flow rr D 3 Interrogation Sequence Start Drive eee D 4 Operator Command scssi otini ieas ieaie D 4 Glossary BBU nieda unnie edn ERR Red ba e NS G 1 Bad Block Table or Bad Data Table oeiee G 1 Battery Backup Unit 0 0 2 eee eeeeeeeseeeeeneeeeeeeneeeeeeeeseeeseneseneneseneensees G 1 Cache acticin aite aiia ein enu n och er rites G 1 Cache Flush x re tete ne eta nie e ees G 1 Cache Line SIZ amp sti x coercet eec Ed ette trece tek G 1 Channel sss nre dte thence ace Mr petere atl G 2 Consistency Check ree ees G 2 Disk Failure Detection eese G 2 vi DACCF User s Manual Disk Media Error Management ssee G 2 Drive Groups or Drive Packs see G 3 Hot Replacement of Disks Hot Swap eee G
24. 5 Navigating within DACCF 2 36 DACCF User s Manual Chapter 3 Administering the Array Overview During the operational life of the array you may have a need to make additions or changes to certain properties of the configuration while retaining the existing configuration For example you may want to increase the capacity of the array or drive group or create new system drives Alternatively you may want to change the write policy for a defined system drive After a power or system failure the data on the array s system drives should be verified and if necessary repaired This section explains how to accomplish these and other tasks Viewing and Updating the Existing Configuration From the Main menu use the View Update Configuration option to view edit or update an existing array configuration Select View Update Configuration from the Main menu to perform any of the associated activities Figure 3 1 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX ttn Firmware n nn n n Main Menu H1 Automatic Configuration a Heu Configuration 44 Rebuild H5 Initialize System Drive 66 Consistency Check B7 Tools AB Select DACI6H H9 Advanced Functions Choose this option to view edit write policy add additional System driue z add Standby drive s to existing configuration Figure 3 1 View Up
25. ACCF User s Manual Administering the Array Using Options on the Tools Menu Many of the functions necessary to ensure continued data availability before during and after a drive is replaced are found in the Tools menu Activate the Tools menu Figure 3 9 by selecting Tools from the Main menu MYLEX Disk Array Controller nfiguration Utility Version mmddyy annel nn Target DACO6HXX in Firm n Main Menu Automatic Configuration Neu Configuration Vieu Update Configuration Rebuild Initialize Bystem Drive Consistency Check 47 Tools B8 Select DACI64H B9 Advanced Functions Choose this option to perform special operations like low level format of physical drive s backup restore print and clear the existing configuration Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 3 9 Tools Option The Tools menu will appear Figure 3 10 Tools 1 Had Block Table Error Counts Format Drive Hake Online Backup Restore conf Clear Configuration z 3 4 5 Kill Drive 6 7 8 Print Configuration Figure 3 10 Tools Menu Viewing the Bad Block Table A bad block is defined as a section on a physical disk which cannot reliably store information Viewing the table applicable for firmware versions below 3 x to inspect the number and location of bad blocks can be used to Manual No 771953 3 11 Using Opti
26. ACCF to a boot disk I don t even havea second floppy drive Putting DACCF on a bootable floppy disk is suggested merely as a convenience It s not an absolute requirement Having a boot disk with DACCF just makes life easier when installing the array for the first time or in the event that a situation occurs where the array cannot be accessed otherwise Are there command line switches or arguments for DACCF See Appendix C B 4 DACCF User s Manual Appendix C Command Line Arguments The diskette based version of DACCF can be started with additional command line arguments or parameters These parameters and their functions are presented below Multiple arguments can be supplied if separated by a space The syntax for supplying the arguments is as follows DACCF argumentl argument2 argument3 WARNING Some command line arguments can potentially cause data loss if used improperly Table C 1 DACCF Parameters Parameter Function o This is used to restart DACCF after it locks up or crashes as a result of an invalid configuration This option overrides the problem and allows DACCF to restart and reread the configuration S This is used to configure the DAC960S when you are using serial port COM to configure the array A null modem cable must connect the COM port of the computer to the serial interface on the DAC960S All communication with the controller is then accomplished via the serial link
27. CSI drives in the array are started spun up There are three different Spin up modes that may be selected by the user The default mode setting is Automatic Automatic This spin up mode causes the controller to spin up all connected drives until every drive in the array is spinning The controller then interrogates each drive and confirms that the drive is ready for use The interrogation process repeats until all drives have been verified The default is set to the Number of Devices per Spin value at an interval indicated by the Delay value see below On Power This spin up mode assumes that all drives are already spinning and proceeds to interrogate the drives in the same manner as described for Automatic mode On Command This spin up mode causes the controller to wait for a spin up command from the host It then proceeds to spin up the drives in the same manner as described for Automatic mode Number of Devices Per Spin Specify the number of drives to spin up Values range from 1 to 6 Delay After the controller completes its initialization process the delay value defines the number of seconds before the first disk interrogation request is issued to the array Delay values range from 0 to 30 in six second increments Manual No 771953 2 13 Low Level Formatting the Drives Low Level Formatting the Drives This step is usually optional Most drives ship with low level formatting already performed by the manufacturer H
28. No 771953 3 9 Running a Consistency Check Choose Select System Drive from the Consistency Check menu Figure 3 8 Consistency Check 1 Select System Drive Z Start Check Figure 3 8 Consistency Check Menu The Consistency Check screen will appear Use the cursor keys to select a particular redundant system drive to be checked for consistency Note Selecting a non redundant system drive for a consistency check will result in an error message as such drives cannot be checked in this manner Press Esc to return to the Consistency Check menu Select Start Check from the Consistency Check menu A confirmation box will appear asking if you want to automatically restore consistency to the drive Select YES to restore consistency to the selected system drive Be aware that potential data loss could result from this action Select NO to cancel the restoration of consistency between the data and parity information contained on this system drive If you are unsure that you have a backup copy of the data on this system drive select the NO option make a backup of the information on the system drive and then perform the consistency check Press the Enter key to start the process The consistency check status screen will appear showing the status of the operation At the conclusion of the check a message indicating success will be displayed Press any key to return to the Main menu D
29. One and only one of its SCSI drives is not online A logical drive is considered critical because any failure of another of its SCSI drives may result in a loss of data Note I O operation can only be performed with system drives that are online or critical Offline A Logical Drive is in an offline state if No data can be read from it or written to it System commands issued to offline logical drives are returned with an error status no operations can be performed on offline logical drives A logical drive can be offline under one of two situations described below tis configured with a redundant RAID level 1 3 5 or 0 1 and two or more of its SCSI drives are not online or tis configured at RAID level 0 JBOD or in a spanned set and one or more of its SCSI drives are not online Glossary 4 DACCF User s Manual Glossary Logical Drives See System Drives Mirroring Refers to the 100 duplication of data on one disk drive to another disk drive Each disk will be the mirror image of the other Pack See Drive Groups or Drive Packs Parity See Rotated XOR Redundancy RAID RAID stands for Redundant Array of Independent Disks Mylex Disk Array Controllers implement this technology to connect up to 7 SCSI devices simultaneously on each channel for firmware versions below 3 0 and up to 15 SCSI devices per channel for firmware 3 0 and above Several different fo
30. RAID Level 3 The RAID Level selection menu pops up Figure 2 22 Use the cursor keys to select a RAID level appropriate for the drive group The cursor will only move to a valid RAID level allowed by the number of drives in the selected group The number of drives in a drive group is also known as the stripe width of the drive group Press the Enter key to select the RAID level for this system drive Table 2 4 presents the minimum number of drives necessary to support each RAID level Table 2 4 Drives per drive group and supported RAID levels Number of Drives RAID Levels Available 1 Mylex RAID Level 7 also known as JBOD 2 0 1 3 or more 0 3 5 0 1 also known as Mylex RAID Level 6 Manual No 771953 2 27 Manual Configuration Note If you are using DAC firmware 4 x or above the RAID Level selection menu will contain an additional menu option called RAID 3 4 Define the size of this system drive in the Enter Size MB popup By default the maximum possible size for the system drive you re defining is displayed To accept the default capacity press the Enter key To enter a value less than or equal to the default size type the value and press the Enter key 5 A window with a summary of this system drive s settings and a confirmation dialog box is presented Figure 2 23 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy
31. Rebuild Add Capacity Rate The rebuild add capacity rate is a relative indication of how much time the controller devotes to a rebuild or add capacity operation Integer values from 0 50 can be defined For low rebuild add capacity priority and high array performance specify a value of 0 For high rebuild add capacity performance and reduced array performance during rebuild select 50 Controller Read Ahead In DAC firmware below version 2 6 the Controller Read Ahead function improves data retrieval performance of sequential loads by allowing the controller to read into cache a full stripe of data at a time This greatly improves the percentage of cache hits 2 8 DACCF User s Manual Preparing the Array For example if the stripe size is set to 8K and the host requests 1K of data when this function is enabled the controller will read ahead the full 8k When the host requests the next 1K block that data will already be in the controller s cache Note Users of DAC firmware version 2 6 and above should be sure that this option is disabled so that the controller will use its adaptive read ahead caching Firmware below version 2 6 does not possess adaptive read ahead caching so this function should remain enabled during normal controller operation Segment Size The Segment Size function available in DAC firmware version 2 6 and above is set in conjunction with stripe size and represents the size of the data chunk in cont
32. YLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX ttn Firmware n nn n n Tgt Channel Number 1 Tools 1 Bad Block Table 2 Error Counts 3 Format Drive Hake Online Kill Drive Backup Restore conf Clear Configuration Print Configuration s Co E fo Press F2 to View full Display Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Previous Menu Figure 2 10 Tools menu 2 Determine your next step by viewing the status of all devices on the left side of the screen If all devices show RDY ready status you don t need to low level format Press Esc to return to the Main menu and skip the rest of this section If any device shows UNF unformatted status go on to the next step 3 Select Format Drive from the Tools menu The highlight bar will be positioned on the first device on the first channel of the array 4 Select the drive to format by moving the highlight cursor to the desired drive and pressing the Enter key 5 A dialog box confirming the format operation will appear Select YES to include the drive in a format operation and press the Enter key The confirmation box will clear and the drive state will change to FMT Select NO to exclude a drive which has been selected for formatting Manual No 771953 2 15 Low Level Formatting the Drives 6 Atthis point s
33. al capacity of the drive group on which it resides Maximum size of a system drive is 32GB when using DAC Firmware versions below 2 6 or 2TB terabytes when using firmware versions 2 6 and above Up to eight 8 system drives can be created per controller with DAC Firmware versions below 2 6 up to 32 system drives for firmware 2 6 and above Each system drive has a RAID level which is selectable subject to the number of disks in the system drive s drive group A system drive has selectable write policy write back or write through To create a System drive follow these steps 1 Select Define System Drive from the New Configuration menu Figure 2 20 Meu Conf iguration 1 Define Pack 2 Define System Drive Figure 2 20 New Configuration Define System Drive 2 26 DACCF User s Manual Preparing the Array The System Drive Definition menu Figure 2 21 will appear This screen displays the existing arranged drive groups System Drive Definition menu and System Drive Table which should be empty as there are no defined system drives As system drives are defined entries are added to this table System Drive Definition 1 Create System Drive Z Toggle Write Policy Figure 2 21 System Drive Definition Menu 2 Select Create System Drive from the System Drive Definition menu The first arranged pack is selected RAID Level Figure 2 22 Selecting the
34. ame size or larger and with the same SCSI ID and the data needs to be rebuilt on this newly installed physical drive Use the Rebuild option on the Main menu for this purpose 48 Note Normally a rebuild operation will also be supported by Mylex utilities for various operating systems and as such this DACCF option may not have to be used To rebuild a physical drive do the following 1 Select Rebuild from the Main menu Figure 3 5 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX in Firmuare n nn n n Main Menu Bi Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration H4 Rebuild H5 Initialize System Drive B6 Consistency Check B7 Tools B8 Select D CI5A B9 Advanced Functions Choose this option to rebuild a replaced DEAD physical drive The replaced physical drive should have been connected and powered on before invoking this Utility for the rebuild to take place Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 3 5 Rebuild Option Manual No 771953 3 7 Rebuilding Drives 2 The rebuild screen will be displayed with the drive matrix Figure 3 6 Tgt Channel Number ID A 1 EI LER I JUD Figure 3 6 Drive Rebuild Matrix Using the cursor keys select the drive to be rebuilt Normally the drive to be rebuilt wi
35. appear System Drive Definition 1 Create System Drive 2 Toggle Write Policy Figure 3 3 System Drive Definition Menu 3 2 DACCF User s Manual Administering the Array Select Toggle Write Policy from the System Drive Definition menu The cursor will move to the system drive definition table Position the cursor on the system drive of interest and press the Enter key to change the write policy for the selected drive Repeat step 3 above to select and change the write policy for other system drives Press the Esc key to return to the System Drive Definition menu Make other changes as described below or proceed to Saving the Updated Configuration to Memory on page 3 6 Creating New Standby Drives To assign a new physical disk to standby hot spare status do the following 1 2 Select Define Pack from the View Update Configuration menu Verify that the status of the new device is RDY If the status of a new device is set to UNF the device requires low level formatting 8 Note In large configurations multiple standby drives may be created for an extra level of protection When one or more physical disks has a status of RDY press the Esc key to return to the View Update Configuration menu Press the Esc key again DACCF will notice drives available for standby duty and ask if you want to save the configuration Select YES to save a new configuration and create standby dri
36. ay Controller Configuration Utility Version n m mmddyy n Channel nn Target DACO6HXX ttn Firmuare n nn n n Edit Uieu Parameters arduare Parameters Physical Parameters SCSI Xfr Parameters Startup Parameters Choose this option to view or edit the controller s changeable Hardware features like batteru backup Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Previous Menu Figure 2 4 Edit View Parameters Menu 8 Note Different Mylex adapters support different Advanced functions Not every function listed below may be available to your controller Manual No 771953 2 5 Setting Controller Parameters for Your Application Any changes to controller parameters from the Advanced Functions menu or one of its sub menus can be saved when exiting the Advanced Functions menu To exit the Advanced Functions menu do the following Press the Esc key A confirmation box will appear Select YES to save the new parameter settings The parameters will be saved and you will return to the Main menu Select NO to retain the parameter settings in effect before the Advanced Functions menu was entered Any changes made will not be applied and you will return to the Main menu Press the Esc key to return to the Advanced Functions menu WARNING Many of the advanced functions can put any data stored on the array at risk if not delete it altogether Such f
37. but not currently included in a drive group DED Disk is dead or has been manually taken offline SBY Disk is a hot spare standby drive ONL Disk is operational and is included in a group FMT Disk is being low level formatted 2 22 DACCF User s Manual Preparing the Array Table 2 3 Device identification and status Device Display Device Status WOL Disk is part of a redundant drive group and is in the process of being rebuilt from data and or parity on other drives in the drive group UNF Disk needs to be low level formatted TAP Device is a tape drive and will not be included in any DACCF operations CDR Device is a CD ROM drive and will not be included in any DACCF operations 5 Press the Enter key to include the highlighted disk device as part of the drive group When a disk is selected for inclusion in a drive group a pack identifier A B C and disk index 0 1 2 are assigned and the disk status changes to ONL 6 Repeat the previous two steps for as many drives as you want to include in a single drive group 8 Note Drive groups can include disks on different channels if the array has multiple channels and disks are connected to each channel The number of drives in a drive group will determine the allowable RAID levels for all of the system drives created in that drive group No more than eight physical drives can be included in a drive group To use more than eig
38. ce information 2 25 manual configuration 2 21 E Error conditions D 1 Configuration Checksum Error D 2 Installation Abort D 1 Interrogation Sequence Start Drive D 4 Media Error Recovery Flow D 3 Operator Command D 4 SCSI Busy Status D 3 SCSI Sequence Error D 3 Timeout on a Command D 3 Error counts 3 13 Exiting DACCF 2 33 Expanding capacity of a drive group 3 4 F Frequently asked questions B 1 H Hard errors 3 14 Hardware parameters 2 6 automatic rebuild management 2 7 operational fault management 2 7 hot spare 3 5 I Installing DACCF 1 2 Manual No 771953 Index 1 J JBOD drive 3 4 Jump keys 2 34 L Low level formatting 2 14 M Main menu 2 35 Manual Configuration 2 21 Miscellaneous errors 3 14 MORE 3 4 Restrictions 3 4 3 5 Mylex Online RAID Expansion 3 4 N Navigating within DACCF 2 33 Cursor keys and jump keys 2 34 Selecting an item 2 35 Using a mouse 2 35 Navigating withing DACCF Exiting a menu 2 35 New configuration 2 21 o ONL 3 5 Overview Administering the Array 3 1 Preparing the Array 2 1 P Pack definition screen 2 22 Parity errors 3 13 PCI RAID DAC support files A 1 Physical parameters 2 8 controller read ahead 2 8 logical sector size 2 11 rebuild add capacity rate 2 8 segment size 2 9 stripe size 2 10 Preparing the array 2 1 Printing the configuration 3 17 Rebuilding drives 3 7 Restoring a configuration 3 16 restriping 3 5 S Saving a configuration 2 29
39. date Configuration Option The View Update Configuration menu is displayed Figure 3 2 Manual No 771953 3 1 Viewing and Updating the Existing Configuration View Update Conf iguration 2 Define System Drive 3 dd Drive to Last Pack 1 Define Pack Figure 3 2 View Update Configuration Menu Use this option to make additions to the configuration while retaining the existing configuration and any data that is resident on system drives in the existing configuration The following functions are available Change the write policy of any system drive from write back to write through and vice versa The write policy can be changed at any time Create new standby drives If new physical drives are being added they can be designated as standby drives Create new drive groups and system drives Existing standby drives and new physical drives can be assigned to new drive groups for subsequent use in the definition of system drives Expand the capacity of the most recently created drive group View the existing configuration All array information including drive groups arranged groups system drives RAID levels and write policies for system drives is displayed Changing the Existing Write Policy To change an existing system drive s write policy do the following 1 Select Define System Drive from the View Update Configuration menu The System Drive Definition menu Figure 3 3 will
40. drives were added to this drive group in the order in which they are listed from left to right In the example above the drive with SCSI ID 0 was added first followed by the drive set to SCSI ID 1 followed by the drive with SCSI ID 2 In the section of the configuration report entitled System Drive Information the column Phy Size refers to the amount of space on the physical drive group which is occupied by a particular system drive The column Eff Size refers to the capacity of the system drive as presented to the operating system with RAID levels taken into account In most cases the numbers will be different with the Eff Size being the lesser of the two values 3 18 DACCF User s Manual Appendix A DACCF File List Mylex Disk Array Controllers which do not have DACCF resident on the BIOS are shipped with a number of software support files on a distribution diskette that is formatted for use with MS DOS The table below displays the structure and content of the distribution disk for PCI RAID DAC product families PCI RAID DAC Products Table A 1 PCI RAID DAC Distribution Disk Directory Filename DACCFG DACCF EXE DACD EXE DOS ASPIDAC SYS DACDRVR SYS BTCDROM SYS UTILS DAC960FL EXE Manual No 771953 A 1 A 2 DACCF User s Manual Appendix B Frequently Asked Questions How do I set up a standby drive using DACCF When initially creating the drive groups do not include
41. e Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 2 2 DACCF Main Menu Setting Controller Parameters for Your Application Each Mylex Disk Array Controller is shipped from the factory with default settings which have been found to work well in a majority of applications and environments However no two environments are the same and you may want to modify certain hardware settings before continuing with the preparation of your array Consult Table 2 1 on page 2 4 If you are satisfied with the default settings skip this section and jump ahead to Low Level Formatting the Drives on page 2 14 If not proceed Controller parameters are organized into four categories Hardware Parameters Physical Parameters e SCSI Transfer Parameters Startup Parameters Manual No 771953 2 3 Setting Controller Parameters for Your Application Table 2 1 Controller Parameter Default and Alternative Settings Controller Parameter Default Setting Alternative Settings Hardware Parameters Automatic Rebuild Mgmt Enabled Disabled StorageWorks Fault Mgmt Disabled Enabled Physical Parameters Rebuild Add Capacity rate 50 rebuild high priority O 49 Controller read ahead is Enabled firmware 2 x Disabled automatic above firmware 2 6 Disabled firmware 3 x Enabled Segment Size 8K 2K 4K 8 8K 16K 32K 64K Stripe Size 8K firmware below 2 6 16K 32K
42. e all available drives to create the current configuration 4 Next select the write policy for the system drive that is to be automatically created Figure 2 14 Do uou want to have Mrite Cache enabled 7 u YES Figure 2 14 Selecting the Write Policy Select NO to set the write policy of the system drive to write through Select YES to set the write policy to write back 8 Note A write back policy which stores data in the cache temporarily during writes will result in better performance under light to medium loads such as file servers at the expense of potential fault tolerance In a power failure system crash any data in the cache will be lost unless the cache has a battery backup A write through policy which writes data to the disk AND cache will result in lower performance but no Manual No 771953 2 19 Automatic Configuration data can be lost in a power failure system crash For more information about write policies refer to the Glossary Mylex strongly recommends the use of a battery backup option or an uninterruptable power supply UPS with any disk array configured with the write back policy 5 Once the appropriate option is selected the configuration is saved and a summary screen Figure 2 15 is displayed This summary screen displays the operating parameters for the configuration MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel n
43. e computer Rerun DACCF Configuration Checksum Error If the DAC s firmware is updated this error message may appear the first time DACCF is run after the update process To eliminate the condition 1 Save the default configuration Power cycle the array Reboot the computer 2 3 4 5 Rerun DACCF Restore the configuration from a diskette containing a copy of the previously saved configuration Errors Which Cause a Drive to be Killed There are multiple conditions which will cause the controller to kill or deactivate a drive from read write operations They are as follows DACCF User s Manual DACCF Error Conditions SCSI Sequence Error Whenever a device follows an illegal SCSI phase sequence 1 e an unexpected disconnect the controller resets the SCSI bus and then interrogates all of the drives it expects to be there If all the drives respond properly operation continues If any drive fails to respond the controller kills that drive SCSI Busy Status When a drive gives the controller a BUSY response the controller retries the command If the count of BUSY responses from a drive exceeds a pre set value currently set at 48 the drive is killed Timeout on a Command If a drive does not complete a command issued to it within a pre set timeout period currently set at six seconds the controller resets the SCSI bus interrogates the drive and kills it if the interrogation fails
44. eeeeneneennennneennne G 8 Standby Replacement of Disks Hot Spare ee G 8 Stripe Order u cebat een RR erg ters G 10 Stripe SiZe 2 5 antea ute p RR VICI ORER RS G 10 Stripe Width idet ide cederet G 10 SIripitig o ic iem ss titii tatum ai Ncc Prato ud G 10 System Drives sch seio d DEAE Tett dr re De Ro Ere Deanne G 10 TargeUlD i n ente e DE PORE G 10 Write Back Cache ute dnte ie cepe ct G 11 Write Through Cache eee eee eee eee eee een G 11 Manual No 771953 vii viii DACCF User s Manual Chapter 1 DACCF Quick Start What is DACCF DACCF is an acronym for the Mylex Disk Array Controller ConFiguration utility It is a set of programs used primarily for first time setup of a RAID subsystem connected to a newly installed Mylex Disk Array Controller DACCF utilities provide the necessary software tools needed to get the disk array up and running as well as advanced functions for monitoring controlling and managing controllers and their connected disk array subsystems DACCF software tools are available in one of two formats depending on the Mylex controller product you purchased and the firmware version residing on the controller 1 Asan installable DOS based software utility located on a DACCF Configuration amp Utilities diskette supplied with the Mylex Disk Array Controller OR 2 Asa BIOS resident utility on the Mylex Disk Array Controller Starting DACCF 8 Note Controller
45. em drive will be automatically configured as standby drives If all of the packs are arranged you will return to the New Configuration menu automatically Viewing Device Information To obtain information about any physical disk drive connected to the Mylex Disk Array Controller 1 Select Device Information from the Pack Definition menu 2 Using the cursor keys select the device and press Enter The selected drive s information is displayed in its own window Figure 2 19 Device Information Vendor QUANTUM Model XP343HBHU Revision 81H6 Size 4695 ME Channel A Target 3 Figure 2 19 Getting Device Information The device information window displays the device manufacturer model number firmware revision and size as reported by the SCSI inquiry and read capacity commands The channel to which the device is attached as well as Manual No 771953 2 25 Manual Configuration the SCSI ID of the device are also displayed 3 4 To select another device press any key to return to the drive matrix box and repeat step 2 to select and display the properties of a different device To return to the pack definition menu press the Esc key Defining and Creating a System Drive After drive groups have been defined and arranged they are used to create system drives System drives have the following properties Each system drive has a defined capacity which is less than or equal to the tot
46. er s settings This is the best time to make these optional changes Low level format the array s SCSI drives Most drives are shipped low level formatted but if a SCSI drive appears in DACCF with the status UNF you should low level format the drive with the Format option so that any media defects can be discovered and catalogued Define and configure one or more physical drive groups or packs Either use the automatic configuration option or define your own drive groups also known as packs A drive group is a collection of one or more physical disk drives Create and configure one or more system drives A system drive has a defined capacity RAID level and write policy Up to eight or 32 system drives can be created for the entire array depending on the firmware version Maximum system drive size is 32GB or 2 terabytes also depending on the firmware version Save the configured information After configuring the array save the configuration to the controller Initialize the system drives Initialize all of the system drives that have been configured above Once this process is complete the host operating system may be installed and the file system may be created on the array Manual No 771953 2 1 Selecting a Controller Note If you are unfamiliar with look and feel and navigation within a DOS based user interface refer to the section Navigating within DACCF on page 2 33 near the end of this chapter for assis
47. expressly disclaims liability for any error in this information and for damages whether direct indirect special exemplary consequential or otherwise that may result from such error including but not limited to loss of profits resulting from the use or misuse of the manual or information contained therein even if Mylex Corporation has been advised of the possibility of such damages Any questions or comments regarding this document or its contents should be addressed to Mylex Corporation at the address shown on the cover The following paragraph does not apply to the United Kingdom or any country where such provisions are inconsistent with local law MYLEX CORPORATION PROVIDES THIS PUBLICATION AS IS WITHOUT WARRANTY OF ANY KIND EITHER EXPRESS OR IMPLIED INCLUDING BUT NOT LIMITED TO THE IMPLIED WARRANTIES OF MERCHANTABILITY OR FITNESS FOR A PARTICULAR PURPOSE Some states do not allow disclaimer of express or implied warranties or the limitation or exclusion of liability for indirect special exemplary incidental or consequential damages in certain transactions therefore this statement may not apply to you Also you may have other rights which vary from jurisdiction to jurisdiction Information in this publication is subject to change without notice and does not represent a commitment on the part of Mylex Corporation Changes may be made periodically to the information herein these changes will be incorporated in new editions o
48. f the publication Mylex Corporation reserves the right to make improvements and or changes at any time in the product s and or program s described in this publication It is possible that this publication may contain reference to or information about Mylex Corporation products machines and programs programming or services that are not announced in your country Such references or information must not be construed to mean that Mylex Corporation intends to announce provide or make available such Mylex products programming or services in your jurisdiction About This Manual This manual covers the steps involved to install and use the Mylex Disk Array Controller Configuration Utilities DACCF software This manual is divided into a number of sections presented in the order in which they are needed over the life of your disk array DACCF Quick Start provides a brief introduction to the Disk Array Controller Configuration Utilities describes how to install and start DACCE and provides a core list of DACCF functions Preparing the Array covers array hardware preparation configuration and initialization After completing the steps in this section you can install the operating system for your specific environment Administering the Array describes the tasks that can be done to the array after it has been placed in service This includes array tuning capacity expansion recovery after a power failure management of the arra
49. ffNILEX Disk Array Controller Configuration Utilities Installation Guide and User Manual Part Number 771953 04 Copyright 1998 Mylex Corporation AI Rights Reserved AII contents of this manual are copyrighted by Mylex Corporation The information contained herein is the exclusive property of Mylex Corporation and shall not be copied transferred photocopied translated on paper film electronic media or computer readable form or otherwise reproduced in any way without the express written permission of Mylex Corporation Greetings This manual describes the Mylex Disk Array Controller Configuration Utilities Requests for technical information about this and other Mylex Corporation products should be made to your Mylex authorized reseller or Mylex marketing representative Please Notice Mylex and DAC960 are registered trademarks of Mylex Corporation Global Array Manager and GAM are trademarks of Mylex Corporation MS DOS Windows 95 and Windows NT are trademarks of Microsoft Corporation Other names that are trademarks may be used herein for the purpose of identifying the products or services of their respective owners Unless otherwise noted companies names and data used in examples herein are fictitious Our Policy Although reasonable efforts have been made to assure the accuracy of the information contained herein this publication could include technical inaccuracies or typographical errors Mylex Corporation
50. firmware versions at or above 2 6 the default stripe size is 64K WARNING DATA LOSS will occur after changing the stripe size on a controller with existing logical arrays Always back up all of the drives before making a stripe size change and always reconfigure and initialize the logical array after a new stripe size is saved Once set the stripe size cannot be changed without first copying all of the data off of the array changing the stripe size reinitializing the drives and copying the saved data back onto the array In a large capacity array this operation could take hours and inconvenience many people You should evaluate your needs now and make any changes necessary before the array is placed in service 2 10 DACCF User s Manual Preparing the Array SCSI Transfer Parameters SCSI transfer parameters control the interaction between SCSI devices and the host adapter To change any SCSI transfer parameter below select SCSI Xfr Parameters from the Edit View Parameters menu A dialog box appears requesting that you select the channel whose SCSI transfer parameters you would like to change Note Channels are numbered from 0 For example on a 3 channel board the channel numbers are 0 1 and 2 Type the channel number and press Enter or press Enter for the default The SCSI Transfer Parameters menu appears specifying the appropriate channel Figure 2 7 SCSI Transfer Parameters of Chamel 1
51. he Initialize System Drive screen will appear Figure 2 26 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX ttn Firmuare n nn n n Initialize System Drive us Dry Cc Simultaneous initialization of 8 System Bus Dru 1 drives can be done Using cursor keys move to the required System drive box and hit lt ENTER gt to select TtWARNING Initialization of the System drives WILL destroy data on the drives Select System drive s using cursor keys hit lt ENTER gt XESC gt to Previous Menu Figure 2 26 Initialize System Drives 3 To mark a system drive for initialization highlight a system drive and press the Enter key As multiple system drives can be initialized simultaneously repeat this process until the desired system drives again all drives should be initialized are marked with a check mark 4 Press Esc to return to the Initialize System Drive menu Initialize System Drive Z Start Initialize 1 Select Sustem Drive Figure 2 27 Return to the Initialize System Drive Menu Manual No 771953 2 31 Initializing the System Drives 5 Select Start Initialize from the Initialize System Drive menu A confirmation box will appear Note Once the system drive initialization is started it should not be aborted Select YES to start the initialization of the selected system drives
52. ht drives create two groups that have an equal number of physical drives Then arrange the drive groups Arranging the Drive Groups on page 2 25 to use both drive groups in a single system drive 7 To finish creating a drive group press the Esc key The device highlights disappear but the pack identifier and disk index for each selected device remain 8 Repeat steps 4 7 for as many drive groups as you wish to define To reserve a disk as a standby do not include it in any packs Manual No 771953 2 23 Manual Configuration Select Cancel Pack from the Pack Definition menu to release the drives in a pack highlight any drive in the pack to be released and press the Enter key 9 When you have finished defining drive packs press the Esc key to return to the Pack Definition menu Note If you have included all of the physical drives into a single drive group the drive group will be automatically arranged and the System Drive Definition menu will appear as shown in Figure 2 21 If this is the case proceed to Defining and Creating a System Drive on page 2 26 Changing or Cancelling a Drive Group To change a drive group you must first delete the drive group and then re create the group To delete a drive group select Cancel Pack from the Pack Definition menu Note You can only cancel the most recently created drive group This means that if you ve defined three drive groups and then decide
53. iew Write Back BBT option to view this additional table 3 12 DACCF User s Manual Administering the Array Viewing Device Error Counts The Mylex Disk Array Controllers maintain several tables of disk errors that are encountered during normal operation These tables are called error count tables To view the error counts for a device do the following 1 Select Error Counts from the Tools menu 2 The highlighted cursor will be positioned at the first device on the channel of the lowest numeric value 3 Using cursor keys or a pointing device select any disk device that is displayed 4 The Error Counts Table for that device will be displayed Figure 3 12 Channel ii ES Target ID Parity Errors Soft Errors Hard Errors Misc Errors BEBE Figure 3 12 Error Counts for a Device Error Count Tables can be used to monitor the health of a device and to indicate when a device needs to be repaired or replaced Viewing the error counts for a particular device displays the number of errors in each table for the selected device Error counters have the following properties A maximum of 127 errors can be recorded for each device in each table Error counters can be reset to 0 by power cycling the array controller and upon running DACCF Parity errors A count of the SCSI bus parity errors that occurred while this device was transferring information on the bus Soft errors A count of check co
54. ion number and date The sign on message looks similar to the following DAC nnnn BIOS Version n nn Mylex Corporation This will be followed by Spinning up drives DAC nnnn Firmware Version n nn n n DAC nnnn Memory xMbytes DRAM Press Alt M for BIOS options where nnnn identifies the specific Mylex Disk Array Controller 1 2 DACCF User s Manual DACCF Quick Start 1 Enter the BIOS options menu by pressing ALT M If you type nothing the boot sequence continues BIOS options BIOS enabled CD ROM boot disabled 8 GB driue geometry Configure MDAC Figure 1 1 BIOS Options Menu There are four BIOS options on the BIOS Options menu We are only concerned with Option 4 Configure MDAC Refer to your Disk Array Controller hardware installation guide for details on the other options 2 Select the Configure MDAC option and press Enter to start the BIOS version of DACCF DACCF will locate the Mylex Disk Array Controller and scan the SCSI device chains attached to it If the utility finds more than one controller you will be prompted to select a controller When the DACCF Main menu appears the BIOS utility is up and running Next you will either set controller parameters in the utility or move directly to preparing your array Chapter 2 Manual No 771953 1 3 When to Use DACCF When to Use DACCF DACCF is meant to be used only by persons with managerial rights or supervisory autho
55. isk drive for example upon which to perform specific operations Navigation is normally performed via cursor keys or via a mouse as outlined below Help Box At key points throughout DACCE a help box is displayed when a specific menu choice is highlighted The Help box usually contains a textual description of the functions of the menu item Getting Around Within DACCF Cursor Keys and Jump Keys DACCF makes extensive use of the cursor movement keys on your keyboard these are sometimes called arrow keys and are labeled as 115 on the keyboard for menu navigation These keys position a highlighted bar called the cursor on various items or objects of interest The cursor will only move between valid choices skipping all the invalid choices An alternative and faster method of positioning the cursor while in a menu is via the Jump keys The jump key for any menu item is the single number or character which is displayed brighter than the surrounding text for that item In the example shown in Figure 2 29 the jump keys are A N V R I C T S and F or 01 09 2 34 DACCF User s Manual Preparing the Array When presented with any menu type the jump key associated with a particular item to move directly to the item Firmware versions above 2 6 allow for up to 16 target devices per channel while versions at or below 2 6 allow for up to 8 target devices per channel This difference is reflected in the number of ta
56. ive failure If a difference between the data and its generated parity is detected consistency check can resolve the difference by restoring the parity based on the data Only one system drive may be checked at a time for consistency WARNING If parity is corrupted running consistency check with the restore parity option should correct the error as long as the data is correct However if data is corrupted consistency check with restore parity will not fix the problem Even though we recommend performing Consistency Checks with restore parity often keep in mind that data loss may still occur To verify and if necessary correct the integrity of a particular redundant system drive do the following 1 Select Consistency Check from the Main menu Figure 3 7 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yuy n Channel nn Target DACO6HXX ttn Firmware n nn n n Main Menu Bi Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild H5 Initialize System Drive AG Consistency Check B7 Tools B8 Select DACI64 A9 Advanced Functions Choose this option to verify the consistency of a redundant System drive Consistency may be restored if the System drive is found to he inconsistent Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 3 7 Consistency Check Option Manual
57. ives that are dependent on the failed disk are redundant system drives e g RAID 1 RAID 3 RAID 5 RAID 0 1 Note The standby rebuild will only happen on the SAME controller never across controllers A Standby disk can be created in one of two ways 1 When a user runs DACCF utility all disks attached to the controller that are NOT configured into any drive group will be automatically labeled as standby drives 2 A disk may also be added attached at a later time to a running system and labeled as standby by using the Disk Array Controller Software Kit see appropriate chapters for DAC utilities for a particular operating system During the automatic rebuild process system activity continues as normal System performance may degrade slightly during the rebuild process To use the standby rebuild feature you should always maintain a standby SCSI disk in your system When a disk fails the standby disk will automatically replace the failed drive and the data will be rebuilt The system administrator can disconnect and remove the bad disk and replace it with a new disk The administrator can then make this new disk a standby The standby replacement table has a limit of 8 automatic replacements in any session from power on reset to the next power off reset When the limit of 8 is reached and a disk failure occurs the standby replacement will occur but will not be recorded in the replacement table To clear the
58. l be copied to the floppy disk Select NO to cancel the backup of the configuration You will return to the Backup Restore Conf menu Manual No 771953 3 15 Using Options on the Tools Menu Restore Configuration 1 Select the Restore Configuration option from the Backup Restore Conf menu to restore a configuration to the array from a configuration file on a diskette You ll be prompted to specify the name and location of the file containing the new configuration The filename can be up to 30 characters including the floppy drive prefix and pathname 2 Enter the name of the file and press the Enter key A confirmation box will appear Select YES to restore the configuration The configuration will be copied from the diskette to the array s non volatile memory WARNING Restoration of an array configuration will completely overwrite the contents of the current configuration Therefore any data residing on the array when the new configuration is implemented will be at risk Use this option with caution and then only after the current configuration has been saved to disk as well The new configuration will be in effect when the controller is reset or the array is next power cycled Select NO to cancel the restoration of the configuration You will return to the Backup Restore Conf menu You can only restore configurations with files that were created by the Backup Configuration option If a configuration file is created
59. l make sure that the data on both drives of the mirrored pair is exactly the same For RAID Level 5 redundancy a consistency connect is a function that allows a target SCSI device typically a disk drive that received a request to perform a relatively long I O operation to release the SCSI bus so that the controller can send commands to other devices When the operation is complete and the SCSI bus is needed by the disconnected target again it is reconnected Disk Failure Detection The controller automatically detects SCSI disk failures A monitoring process running on the controller checks among other things elapsed time on all commands issued to disks A time out causes the disk to be reset and the command to be retried If the command times out again the disk could be killed taken offline by the controller its state changed to dead Mylex Disk Array Controllers also monitor SCSI bus parity errors and other potential problems Any disk with too many errors will be killed Disk Media Error Management Mylex Disk Array Controllers transparently manage SCSI disk media errors Disks are programmed to report errors even ECC recoverable errors When a disk reports a media error during a read the controller reads the data from the mirror RAID 1 or 0 1 or computes the data from the other blocks RAID 3 RAID 5 and writes the data back to the disk that encountered the error If the write fails media error on wri
60. ll be indicated by the letters DED for DEAD drive DACCF will ask you if you want to low level format the drive Select YES if this is a new drive that has not been used in this array before allow the drive to be low level formatted before the rebuild takes place Any defined system drives will then be rebuilt on the new drive in sequential order Select NO to skip the low level format and proceed directly to the rebuild of data on the new drive Press the Enter key to initiate the rebuild A rebuild status screen will appear showing the progress of data reconstruction on all of the system drives that are dependent on the selected physical drive System drives are rebuilt sequentially beginning with the system drive with the lowest numerical value At the conclusion of the rebuild a message indicating success will be displayed Press any key to return to the Main menu Note A rebuild fails firmware version lower than 3 x if read errors are encountered on existing physical drives which comprise the system drive The View Rebuild BBT function View Rebuild BBT on page 3 12 reports all such errors 3 8 DACCF User s Manual Administering the Array Running a Consistency Check A consistency check compares the data and parity information on redundant system drives e g system drives with RAID levels of 1 3 5 or 0 1 to ensure that they can continue to function in the event of a physical dr
61. n Target DACO6HXX ttn Firmware n nn n n fiutomatic Configuration 1 5 Number of Sustem drives Raid Level Write Cache Enabled Number of Physical drives 3 Available Capacity 658 HB Standby drive has been created Automatic configuration successfully done Make sure to INITIALIZE System drive HH before exiting this utility Press any key to return to Main Menu Figure 2 15 Automatic Configuration Summary Screen 6 Press any key to return to the Main menu and proceed directly to Initializing the System Drives on page 2 30 2 20 DACCF User s Manual Preparing the Array Manual Configuration Select this option to manually configure the disk array for the first time or to reconfigure the array This option will create a new configuration overwriting any existing array configuration To change the write policy of an existing configuration add additional drive packs or add capacity to the last configured drive pack use the View Update Configuration item on the Main menu see Chapter 3 Administering the Array WARNING Overwriting an existing configuration will result in the complete and irreversible loss of all data stored on disk drives in the array Use this option with caution Defining and Creating Drive Groups To define drive groups follow the procedure below 1 Select New Configuration from the Main menu Figure 2 16 MYLEX Disk Array Controller Configuration Utility Versi
62. n of the array is the initialization of the system drives Mylex recommends that all system drives be initialized immediately after they are created WARNING Failure to initialize a system drive will result in unpredictable drive behavior such as an inability to boot or load the operating system or failure of a consistency check Any data placed on uninitialized system drives is at risk To initialize one several or all recommended system drives follow the steps below 1 Select Initialize System Drive from the Main menu Figure 2 24 n Channel nn Target DACO6HXX in MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy Firmuare n nn n n Main Menu Bi Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild An Initialize System Drive H6 Consistency Check B7 Tools B8 Select D CI5H A9 Advanced Functions 16 Diagnostics Choose this option to initialize one or more System drives sinultaneously Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 2 24 Initialize System Drive Option DACCF User s Manual Preparing the Array 2 Choose Select System Drive from the Initialize System Drive menu Figure 2 25 Initialize System Drive 1 Select Sustem Drive Z Start Initialize Figure 2 25 Initialize System Drive Menu T
63. ndition media errors reported by the device These errors are typically generated when a bad sector on the disk is encountered Manual No 771953 3 13 Using Options on the Tools Menu Such errors are recovered by the controller if the device is part of a redundant system drive by generating the data from the remaining disks or by retrying the operation The bad sector on the device is also eliminated by writing back the data onto the disk and reading to verify since a verify failure results in the reassignment of data to a different sector Hard errors Hardware related errors on the controller The following conditions cause the hardware error count to be incremented for a device e SIOP interrupt for Illegal instruction detected e SIOP interrupt for Gross error SCSI device executed illegal unsupported phase sequence During normal operation the hard error count for any device should be zero Miscellaneous errors Other errors such as A device times out on a command issued to it by the controller Anactive device was busy when the controller attempted to send it a command Backup Restore Configuration Note USERS OF DAC FIRMWARE VERSION 3 0 AND ABOVE may skip this section The configuration on disk feature of firmware version 3 0 and above automatically saves the current configuration to the disk drives without user intervention Should a controller fail the saved configuration is restored to the
64. on n m mm dd yy n Channel nn Target DACO6HXX ttn Firmuare n nn n n Main Menu Bi Automatic Configuration 63 Vieu Update Configuration B4 Rebuild 5 Initialize System Drive H6 Consistency Check B7 Tools B8 Select D CI5A B9 Advanced Functions Choose this option to do a fresh custom configuration Configuring the adapter involves creating pack s arranging the created pack s followed by creating System drive s Figure 2 16 New Configuration Option Manual No 771953 2 21 Manual Configuration Meu Conf iguration 1 Define Pack 2 Define Systen Drive Figure 2 17 New Configuration Define Pack 2 Select Define Pack from the New Configuration menu Figure 2 17 This option is used to define drive groups also called packs The Pack Definition menu will be displayed Figure 2 18 Pack Definition 1 Create Pack 2 Cancel Pack 3 Arrange Pack 4 Device Information Figure 2 18 Pack Definition Menu 3 Select Create Pack to begin grouping the drives into a pack The highlighted bar is positioned on the first device found by the controller on the first channel 4 Use the arrow keys to position the highlighted bar on a disk device identified as RDY Device identification is shown in Table 2 3 Table 2 3 Device identification and status Device Display Device Status RDY Disk is operational
65. one or more drives in a drive group The drive should have a status of RDY After drive groups have been arranged and the configuration saved the excluded drives assume a status of SBY or Standby There s another way to create standby drives and that s detailed below What is the procedure for setting up a RAID 0 1 3 5 0 1 JBOD system See the Overview in Chapter 2 Preparing the Array for a quick summary of the steps A RAID system will require several disks for redundancy How many drives are needed to set up a RAID 0 1 3 5 0 1 JBOD system Table B 1 Drives Required Per RAID Level Minimum Number of Drives RAID Levels Available 1 Mylex RAID 7 also known as JBOD 2 0 1 3 or more 0 3 5 0 1 also known as Mylex RAID 6 I get a message adapter not responding to command What does this mean and what should I do This error indicates a time out condition with a SCSI device either the controller or one of the devices on the SCSI chain To determine the location of the problem remove all cabling from the controller and run DACCF again with the o option If the error persists the controller needs servicing If the error does not reappear then check your devices and cabling Manual No 771953 B 1 The message Error writing configuration has appeared What should I do This message is most commonly displayed when there is no 12V power source to the main logic board of the compu
66. ons on the Tools Menu troubleshoot a failed rebuild operation or can help predict a physical drive failure The Bad Block Table option lets you view the two tables that the controller maintains during both a rebuild process as well as normal operation To view either or both of these tables select Bad Block Table from the Tools menu The View Bad Block Table menu appears Figure 3 11 View Bad Block Table View Rebuild BET Uieu Write Back BBT Figure 3 11 View Bad Block Table Menu Note A bad block table is cleared after viewing Make sure that you record any information either by saving the table to another disk drive or by manually transcribing the information in the table View Rebuild BBT During a rebuild operation data is read from existing redundant drives in the drive group reconstructed by the controller and then written to the replacement drive If a read error on an existing drive occurs during a rebuild the rebuild process will fail under DAC firmware version 2 x In that case one of the existing drives not the replacement drive has errors Select the View Rebuild BBT option to determine which drive has errors View Write Back BBT During normal operation if you have a system drive s write policy set to write back a second bad block table is maintained in the controller s memory This table is updated whenever an error occurs during a read or write operation Select the V
67. ontroller are used system service continues without interruption A message is generated by the system to alert the system operator When a replacement drive becomes available the system operator can remove the failed disk drive install a new disk drive and instruct the controller to rebuild the data on the new drive all without interrupting system operations Once the rebuild is complete the controller will be brought back into a fault tolerant state IBBU See Intelligent Battery Backup Unit Intelligent Battery Backup Unit The Intelligent Battery Backup Unit IBBU is an add on module that provides power to a compatible Mylex Disk Array Controller cache memory in the event of a power failure The battery backup module monitors the write back cache on the controller and provides power to the cache if it Manual No 771953 Glossary 3 Glossary contains data not yet written to the drives when power is lost The controller with the IBBU installed together occupy only one PCI slot on the host backplane Logical Drive States The state of a logical system drive can be either ONLINE CRITICAL or OFFLINE Notice that the same term online is used for both physical and logical drives Online A Logical Drive is in an online state if All of its participating SCSI drives are online Critical A Logical Drive is in a critical state if It has been configured at RAID level 1 3 5 or 0 1 and
68. owever Mylex recommends that you view the status of each device before starting the configuration for the first time If any device carries a status of UNF rather than RDY it should be low level formatted with DACCF before use Low level formatting will completely erase all existing data on the drives and perform a media surface check The procedure for viewing the status of the devices AND performing a low level format is described below WARNING Low level formatting will destroy all existing data on the disk drive 1 Select Tools from the Main menu Figure 2 9 MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX ttn Firmware n nn n n Main Menu Bi Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild H5 Initialize System Drive H6 Consistency Check 47 Tools B8 Select DACI64H B9 Advanced Functions Choose this option to perform special operations like low level format of physical drive s backup restore print and clear the existing configuration Figure 2 9 Tools Option on Main Menu The Tools menu will appear after a short interval Figure 2 10 2 14 DACCF User s Manual Preparing the Array A representation of the physical devices in the array will be displayed on the left side of the screen and the Tools menu appears on the right side of the screen M
69. r drives may be spanned and seen as a single drive This level does not provide data redundancy Mylex RAID 7 8 Note The host operating system drivers and software utilities remain unchanged regardless of the level of RAID installed The controller makes the physical configuration and RAID level implementation Replacement Table A replacement table contains information regarding which SCSI devices have been replaced by others through standby replacement Rotated XOR Redundancy This term also known as parity refers to a method of providing complete data redundancy while requiring only a fraction of the storage capacity of mirroring In a system configured under RAID 3 or RAID 5 which require at least three SCSI drives all data and parity blocks are divided between the drives in such a way that if any single drive is removed or fails the data on it can be reconstructed using the data on the remaining drives XOR refers to the Boolean Exclusive OR operator In any RAID 3 or RAID 5 array the capacity allocated to redundancy is the equivalent of one drive Glossary 6 DACCF User s Manual Glossary SCSI Drive A disk drive equipped with a SCSI interface sometimes referred to as a SCSI Disk Each disk drive will be assigned a SCSI address or SCSI ID which is a number from 0 to 7 0 to 15 under Wide or Ultra SCSI The SCSI address uniquely identifies the drive on the SCSI bus or channel SCSI Drive States
70. rdware compatibility with disk array enclosures that are certified AEMI SAF TE or StorageWorks Fault Management compliant Operational Fault Management The StorageWorks Fault Mgmt TM option monitors and reports drive failures background activity completion status enclosure events etc Enable this function only when Digital StorageWorks Fault Management equipment disk cabinet is installed In all other cases this option should remain disabled WARNING If you enable StorageWorks Fault Management make sure that Automatic Rebuild Management is disabled Manual No 771953 2 7 Setting Controller Parameters for Your Application Physical Parameters Physical parameters define the interaction between the controller and the disk drives To change any physical parameter select Physical Parameters from the Edit View Parameters menu The Physical Parameters menu appears Figure 2 6 Physical Parameters Rebuild Add Capacity rate E Controller read ahead Enabled Segment size K bytes Stripe size K bytes 8 Figure 2 6 Physical Parameters Menu To change a physical parameter do the following 1 Highlight the desired parameter using the cursor keys 2 Press the Enter key to change the value 3 When the correct value is displayed either Repeat steps 1 amp 2 above but for a different parameter or Press the Esc key to return to the Edit View Parameters menu The change will be retained
71. re present choose this option to create one RAID 5 System drive automatically Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 2 12 Automatic Configuration Option 2 Anerror message will be displayed if fewer than 3 or more than 8 drives are detected or if drives of differing capacities are found The Automatic Configuration will then abort If no errors are encountered but a valid array configuration already exists DACCF will warn you that you are about to replace the configuration with the structure created by the Automatic Configuration A confirmation is required to proceed AN Caution If you overwrite an existing configuration by selecting Yes all data will be lost Select YES to proceed overwriting the existing configuration with the automatically generated configuration Select NO in the confirmation box to return to the Main menu with no changes to the array configuration 2 18 DACCF User s Manual Preparing the Array 3 Next select whether you wish to reserve one available unconfigured drive to be used as a standby hot spare drive Figure 2 13 Do you wish to have a Standby drive 7 YES Figure 2 13 Deciding Whether to Reserve a Standby Drive Select YES to set aside one available drive to be used as a standby before all other drives are configured Select NO to choose not to set aside a standby drive Automatic Configuration will us
72. rget IDs available in the left hand window Use F2 followed by PgDn and PgUp to view additional devices on the channels MYLEX Disk Array Controller Configuration Utility Version n m mm dd yuy n Channel nn Target DACO6HXX ttn Firmuare n nn n n Main Menu HZ Meu Configuration 63 Vieu Update Conf iguration B4 Rebuild H5 Initialize System Drive B6 Consistency Check B7 Tools B8 Select D CI5A A9 Advanced Functions If 3 or more Physical drives are present choose this option to create one RAID 5 System drive automatically Use Cursor keys for selection hit lt ENTER gt to select lt ESC to Quit Figure 2 29 DACCF Selecting an Item Once highlighted via either of the above methods an item is selected by pressing the Enter key Exiting a Menu Use the Escape Esc key to return to the previous action or state If you select the wrong menu choice the Esc key will return to the menu Using a Mouse DOS Based Version Only A mouse or other pointing device can also be used to navigate the DACCF menus You ll need to have loaded a mouse driver prior to running DACCF To position the highlight bar on a menu item position the mouse cursor as opposed to the highlighted bar on the item and single click the left mouse button To select an item position the mouse cursor on a highlighted item and single click the left mouse button Manual No 771953 2 3
73. rity These are powerful utilities that must be used properly or data loss can result It is a good idea to have a written plan that identifies the system resources e g devices capacities locations by SCSI channel target ID etc and the desired logical drive configurations LUN sizes RAID types etc before you begin setting up or changing an array configuration You should use DACCF utilities To change default controller parameters before an array is set up To configure and initialize an array during initial system setup before loading the operating system To save the array configuration information to a disk file To perform diagnostics on an array controller DACCF can be used to perform functions beyond those listed above However for most functions involving array or controller configuration monitoring or managing we recommend that you use the Mylex Global Array Manager software 1 4 DACCF User s Manual Chapter 2 Preparing the Array Overview The following is an overview of the steps necessary to prepare an array Each step is described in greater detail later in this chapter 1 Start DACCF Chapter 1 DACCF Quick Start Invoke DACCF from the MS DOS prompt or controller s BIOS Optimize the controller parameters for your application Although the Mylex Disk Array Controller ships from the factory optimized to work in a variety of environments certain changes can be made to the controll
74. rms of RAID implementation have been defined Each form is usually referred to as a RAID level The most common RAID levels supported by Mylex Disk Array Controllers are shown below The appropriate RAID level for a system is selected by the system manager or integrator This decision will be based on which of the following are to be emphasized Disk Capacity Data Availability redundancy or fault tolerance Disk Performance RAID Levels The disk array controllers monitored by this utility support four RAID Advisory Board approved RAID 0 RAID 1 RAID 3 RAID 5 and two special RAID levels RAID 0 1 and JBOD Manual No 771953 Glossary 5 Glossary Level 0 Block striping across multiple drives is provided yielding higher performance than is possible with individual drives This level does not provide any redundancy Level 1 Drives are paired and mirrored All data is 100 duplicated on a drive of equivalent size Level 3 Data is striped across several physical drives Maintains parity information which can be used for data recovery Level 5 Data is striped across several physical drives For data redundancy drives are encoded with rotated XOR redundancy Level 0 1 Combines RAID 0 striping and RAID 1 mirroring This level provides redundancy through mirroring Mylex RAID 6 JBOD Sometimes referred to as Just a Bunch of Drives Each drive is operated independently like a normal disk controller o
75. roller memory that will be read or written at one time The segment size also known as cache line size should be based on the stripe size The default segment size for Mylex Disk Array Controllers is 8K Table 2 2 Segment Sizes for Each Stripe Size Stripe Size Select Segment Size 8k 8K 16K 16K 32K 32K 64K gt 2K 4K 8k 64K a Default Firmware version below 2 6 b Default Firmware version at or above 2 6 c supported only in early firmware versions A large segment size 64K is useful with a 64K stripe size for applications requiring large sequential reads or writes e g video playback from disk It can hinder system performance if files are smaller or if data access is more random than sequential An 8K segment size is best for most applications Manual No 771953 2 9 Setting Controller Parameters for Your Application Stripe Size The Stripe Size function is used to tune the controller performance for a specific environment or application Generally stripe size optimization is as follows Smaller stripe sizes provide better performance for random I O e g RAID 3 RAID 5 network file service or OLTP processing Larger stripe sizes provide better performance for sequential transfers e g RAID 0 RAID 1 0 digital video etc Available stripe sizes are 8K 16K 32K and 64K For firmware versions below 2 6 the default stripe size for Mylex Disk Array Controllers is 8K For
76. s are true about the last created pack the pack with the highest letter value in the list MORE will not be able to add capacity to the pack The pack consists of a single JBOD RAID 7 drive The pack already has eight 8 drives The pack is a spanned pack e A total of 32 system drives have already been configured Alltarget IDs on all channels are used in existing packs 3 4 DACCF User s Manual Administering the Array 2 Use the arrow keys to position the highlighted bar on a disk device identified as RDY ready available or SBY standby hot spare 3 Press the Enter key to include it in the expansion process When a disk is selected for inclusion in the last pack the identifier of the last pack A B C and disk index of the new drive 0 1 2 are assigned and the disk status changes to ONL 4 Repeat the previous two steps for other drives that you want to add to the last pack if any One or both of the following conditions may prevent DACCF from allowing you to select a particular disk device The drive capacity is too small to be used in the pack The pack already has eight 8 drives which may include disk device selections you just made 5 If necessary press the Esc key when you have finished your selection The restriping process is ready to begin and a warning message appears Figure 3 4 Irreversible process Do you want to proceed VES Figure 3
77. s before proceeding to determine which method is more suitable for your installation 48 Note Mylex Disk Array Controllers ship from the factory with no configuration information stored in memory The Automatic Configuration option configures the array with just a few keystrokes and can only be used when the array consists of between 3 and 8 drives Although drives of different sizes may be used in the array Automatic Configuration will only operate upon drives of the same physical size The Automatic Configuration option creates an array with the following properties e All of the physical drives are contained in a single drive group The drive group is defined as a single RAID level 5 system drive e Standby hot spare drive status present or absent and the write policy write back or write through caching is selected during the configuration process The system drive number is 0 1 Select Automatic Configuration from the Main menu Figure 2 12 Manual No 771953 2 17 Automatic Configuration MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX in Firmware n nn n n Main Menu A1 Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild 5 Initialize System Drive H6 Consistency Check B7 Tools B8 Select D CI5A B9 Advanced Functions If 3 or more Physical drives a
78. swer YES to save the updated configuration although in effect nothing has been changed B 2 DACCF User s Manual 10 11 12 13 14 15 Frequently Asked Questions Exit DACCF Connect the replacement drive Invoke DACCF Select View Update Configuration from the Main menu Press the Esc key Answer YES to save the new configuration and the unconfigured drive s as standby drives Verify that the drive is a standby drive by selecting View Update Configuration again from the Main menu The replacement drive should have a status of SBY I ve replaced a drive that the controller made dead Now what do I do to recover the data The following procedure will only work for replaced drives that are part of a RAID 1 3 5 or 0 1 drive group Using the Main menu do the following l 2 Select Rebuild Highlight the drive that has been replaced The status should read DED Press the Enter key DACCF will ask you if you want to low level format the drive If this is a new drive that has not been used in this array before allow the drive to be low level formatted before the rebuild takes place by answering YES Answering NO will skip the low level format and proceed directly to the rebuild of data on the new drive Any defined system drives will then be rebuilt on the new drive in sequential order How do I change the write policy on a existing configuration To change
79. tance Selecting a Controller In Chapter 1 you started the DACCF utilities DACCF operates upon a single Mylex Disk Array Controller at a time If you have a single controller in your system DACCF will automatically detect and select it You can ignore this section and proceed to Setting Controller Parameters for Your Application on page 2 3 If more than one controller is detected in your system DACCF will ask you which controller to perform operations upon Figure 2 1 Select DACIGA DA C1164P CPCI 1 FW 4 64 8 8 DACIBEPG CPCI Z FU 4 HB BH 3 D Figure 2 1 Select Which Controller to Operate Upon Select the desired controller and after a brief interrogation of the devices attached to that controller the Main menu Figure 2 2 will appear Note You can select a different controller at any time by using the Select DAC960 option on the Main menu 2 2 DACCF User s Manual Preparing the Array MYLEX Disk Array Controller Configuration Utility Version n m mm dd yy n Channel nn Target DACO6HXX ttn Firmuare n nn n n Main Menu A1 Automatic Configuration HZ Meu Configuration 63 Vieu Update Configuration B4 Rebuild 5 Initialize System Drive B6 Consistency Check B7 Tools B8 Select D CI5A B9 Advanced Functions If 3 or more Physical drives are present choose this option to create one RAID 5 System drive automatically Us
80. te the controller issues a reassign command to the disk and then writes the data to a new location Since the problem has been resolved no error is reported to the system When a disk reports a media error during a write the controller issues a reassign command to the disk and writes the data out to a new location on the disk Glossary 2 DACCF User s Manual Glossary Drive Groups or Drive Packs A group of individual disk drives preferably identical that are logically tied to each other and are addressed as a single unit In some cases this may be called a drive pack when referring to just the physical devices Up to eight 8 drives can be configured together as one drive group All the physical devices in a drive group should have the same size otherwise each of the disks in the group will effectively have the capacity of the smallest member The total size of the drive group will be the size of the smallest disk in the group multiplied by the number of disks in the group For example if you have 4 disks of 400MB each and 1 disk of 200MB in a pack the effective capacity available for use is only 1000MB 5 200 not 1800MB Hot Replacement of Disks Hot Swap The design of the Mylex Disk Array Controllers allows for the replacement of failed hard disk drives without interruption of system service In the event of a SCSI drive failure on a properly configured system where the data redundancy features of the c
81. te Through Cache Refers to a caching strategy whereby data is written to the SCSI drive before a completion status is returned to the host operating system This caching strategy is considered more secure since a power failure will be less likely to cause loss of data However a write through cache results in a slightly lower performance Manual No 771953 Glossary 11 Glossary Glossary 12 DACCF User s Manual A Add Drive to Last Pack 3 4 3 5 Advanced Functions 2 4 Automatic Configuration 2 17 B Backing up a configuration 3 14 3 15 Bad block table 3 11 C cache line size 2 9 Changing an existing write policy 3 2 Clearing the configuration 3 17 Command line arguments 1 2 C 1 Consistency check 3 9 Controller parameters setting 2 3 Creating new drive groups and system drives 3 4 Cursor keys 2 34 D DACCF description 1 1 exiting 2 33 file list A 1 installing from diskette 1 2 starting 1 1 starting BIOS version 1 2 when to use 1 4 DACCF screen Actions bar 2 34 Device representations 2 34 Help box 2 34 Menus and dialog boxes 2 34 Title window 2 33 data migration 3 5 Device startup parameters 2 12 initial delay 2 13 number of devices per spin 2 13 Index spin up option 2 13 Device status 2 22 Drive groups adding capacity 3 4 arranging 2 25 automatic configuration 2 17 changing or cancelling 2 24 creating a standby or hot spare disk 2 24 creating new 3 4 defining and creating 2 21 devi
82. teps 4 and 5 can be repeated for other disk devices in the array that should be included in the low level format After all devices have been selected for formatting press the Esc key A confirmation box will appear Select YES to format the drives and press the Enter key The drive low level format process will commence Select NO to abort the format process and press the Enter key The selected drives will not be formatted and you will return to the Tools menu 8 If a device cannot be low level formatted a message will appear Figure 2 11 indicating the channel and ID of the device The device should be replaced and the low level format process repeated for that device FURMAT Failed on Device Channel Target ID 1 Press any key to continue Figure 2 11 Device Error During Format 9 To return to the Main menu from the Tools menu press the Esc key 2 16 DACCF User s Manual Preparing the Array Automatic Configuration After the devices have been formatted if necessary the first step in configuration is deciding whether to configure drive groups automatically or manually Automatic configuration has certain limitations but is the easiest and quickest way to prepare an array for operation Manual configuration gives you complete control of the array s design but will take longer to complete and requires more user knowledge than an automatic configuration Mylex recommends that you read both section
83. ter system Newer systems have 3 3V connectors as well and occasionally the 12V line is not attached to the board Check your internal power connectors first There may also be a problem with the Non volatile RAM NVRAM or the EEPROM on the controller The configuration is written to both of these memories If you re sure that you have 12V power try changing the EEPROM or the NVRAM I get an error message saying Initialization failed What should Ido This condition occurs when a drive is not responding to controller commands during the initialization process Check cables and termination Verify the operation of the individual devices using the Tools menu and if necessary replace the malfunctioning drive s I have a hot spare configuration One of my disks failed and the hot spare took over l ve replaced the failed disk but cannot get the controller to recognize the replacement disk which can now become the hot spare What should I do Follow these steps 1 Disconnect the replacement drive 2 Invoke DACCF 3 Select View Update Configuration from the Main menu 4 Select Define System Drive from the View Update Configuration menu eA Select Toggle Write Policy from the System Drive Definition menu 6 Press the Enter key to change the write policy for the first or any system drive then highlight the same drive and press the Enter key to change it back to its original value 7 Press the Esc key twice 8 An
84. that you want to change the contents of the first drive group you ll have to delete all three groups the current or third group then the second group and finally the first group Before deleting any drive groups though you may want to write down the contents of the drive groups that you do not want to change When you ve changed the first group you can then quickly recreate the second and third groups from your notes Creating a Standby or Hot Spare Disk To create a standby or hot spare drive do not include the device as a part of any drive group The device status will change from RDY to SBY when the configuration is saved to memory Saving the configuration is explained later in this chapter 2 24 DACCF User s Manual Preparing the Array Arranging the Drive Groups Next arrange the drive groups that you have created by selecting Arrange Pack from the Pack Definition menu The pack arrangement screen will be displayed Move the highlighted bar to any drive of the desired group and press the Enter key to arrange it The drive group will be added to the table on the lower right side of the screen which lists the drive group s pack identifier the number of drives in the group and the capacity of the drive group This table is called the pack arrangement table Note The drives belonging to unarranged packs drives that are not part of any pack or drives of arranged packs that have not been configured into any syst
85. the cursor keys to highlight the desired system drive 3 Press the Enter key to toggle or change the write policy for that system drive The allowed policies are WRITE THRU and WRITE BACK 4 Repeat steps 2 and 3 above to select and change write policies for other system drives if any 5 When the write policies are set correctly on all desired system drives press the Esc key to return to the System Drive Definition menu Saving the New Configuration Once all of the system drives are defined the configuration should be saved to the controller s memory To save the configuration 1 From the System Drive Definition menu press the Esc key twice 2 ASave Configuration confirmation dialog box will be displayed Select YES to save the configuration You will return to the Main menu Select NO to discard all changes made to drive groups group arrangements system drives and write policies You will return to the Main menu Manual No 771953 2 29 Initializing the System Drives Press the Esc key to return to the New Configuration menu Any changes are retained and additional modifications can be made However the configuration will need to be saved before proceeding to the last step of array preparation This completes the configuration process To finish preparing the array initialize the system drives as described in the following section Initializing the System Drives The last step in the preparatio
86. unctions are noted in the manual but Mylex recommends that you perform the modifications afforded by the advanced functions on an array that has not been loaded with a file system and data Additionally inappropriate changes to the controller parameter settings can result in degraded performance Hardware Parameters Hardware parameters control specific controller functions To change any of the hardware parameters below select Hardware Parameters from the Edit View Parameters menu The Hardware Parameters menu appears Figure 2 5 Harduare Parameters Automatic Rebuild Management Enabled StorageWorks Fault Mgmt TH Disabled Figure 2 5 Hardware Parameters Menu 2 6 DACCF User s Manual Preparing the Array To change a hardware parameter do the following 1 Highlight the desired parameter using the cursor keys 2 Press the Enter key to change the value 3 When the correct value is displayed either Repeat steps 1 amp 2 above but for a different parameter or Press the Esc key to return to the Edit View Parameters menu The change will be retained Automatic Rebuild Management The Automatic Rebuild Management option refers to the function of the same name It detects the removal of a failed drive and performs an automatic rebuild after a replacement drive is installed into a redundant fault tolerant logical array RAID 1 3 5 and 0 1 Automatic Rebuild Management requires ha
87. ve is in a rebuild state While it is in the process of being rebuilt During this process data is regenerated and written to the disk drive This state is also referred to as Write Only WRO Segment Size The Segment Size function available in DAC firmware version 2 6 and above is set in conjunction with stripe size and represents the size of the data chunk that will be read or written at one time Under DACCF the segment size also known as cache line size should be based on the stripe size you selected The default segment size for Mylex Disk Array Controllers is 8K Session Refers to the period of time between any two consecutive system shutdowns System shutdown may be either a power off on or a hardware reset Standard Disk Drive This term refers to a hard disk drive with SCSI IDE or other interface that is attached to the host system through a standard disk controller Standby Replacement of Disks Hot Spare The Standby Replacement or Hot Spare is one of the most important features the controller provides to achieve automatic non stop service with a high degree of fault tolerance The rebuild operation will be carried out by the controller automatically when a SCSI disk drive fails and both of the following conditions are true A standby SCSI disk drive of identical size is found attached to the same controller Glossary 8 DACCF User s Manual Glossary Allofthe system dr
88. ve s Select NO to avoid creating the standby drive s The current configuration will be retained and the drive s that are not part of a drive group will remain in the RDY state Manual No 771953 3 3 Viewing and Updating the Existing Configuration Creating New Drive Groups and System Drives To create new drive groups and system drives do the following 1 Select Define Pack from the View Update Configuration menu 2 Follow the instructions presented in Manual Configuration in the previous chapter beginning at Step 3 This includes creating and arranging drive groups defining system drives and setting RAID levels and write policy Expanding the Capacity of a Drive Group DACCF includes Mylex Online RAID Expansion MORE technology a method for adding capacity to an existing drive group pack Instead of deleting a pack and recreating it with the additional drive s a function called Add Drive to Last Pack allows the user to select one or several drives to add to the last pack that was created Note In MORE under DACCE only the last pack can be expanded restriped Packs that were created prior to that pack are not available for automatic capacity expansion using MORE To expand the capacity of the last created drive group do the following 1 Select Add Drive to Last Pack from the View Update Configuration menu to request the capacity expansion process If any of the following condition
89. y Version n m mmddyy n Channel m Target DACO6BXX in Firmuare n nn n n Tgt Channel Humber Tools 1 Bu 1 Had Block Table m ag 2 Error Counts B urs 3 Format Drive ONT gg Make Online Ez Kill Drive ONL gg Backup Restore conf D3 Clear Conf iguration Print Configuration Al DATA will be LOST Proceed with Format 7 NO VES Choose YES to Format MO or lt ESC gt to Previous Menu Figure 2 28 DACCF Screen Areas and Objects Title Window Throughout DACCE a title window on the top of the screen will display the utility title version number and date MYLEX Disk Array Controller Configuration Utility Version n nn mm dd yy In addition the currently Manual No 771953 2 33 Navigating within DACCF selected controller s name slot number and firmware version turn number are displayed n Channel nn Target DACnnnXX n Firmware n nn n n Actions Bar Each screen uses the bottom row of the display to indicate allowed operator actions Menus and Dialog Boxes Each screen has either a menu of items that can be selected or a dialog box requiring a specific action Device Representations At certain points in DACCF a representation of a particular device a disk array for example will be displayed along with a menu and or dialog box Often DACCF permits you to navigate within the device to select specific objects a d
90. y after a hardware malfunction tools and diagnostics For information on setting the controller s SCSI termination jumpers and connecting the disk drives consult the appropriate Mylex Disk Array Controller hardware installation guide Conventions Throughout the manual the following conventions are used to describe user interaction with the product bold The user must enter the bold text exactly as shown a Press the Enter key Enter Press the key labeled Enter or Delete etc Note Supplementary information that can have an effect on system performance A Caution Notification that a proscribed action has the potential to adversely affect equipment operation system performance or data integrity WARNING Notification that a proscribed action will definitely result in equipment damage data loss or personal injury Contents Chapter 1 DACCF Quick Start Whatis DAGCE2 2c ee cce ect t pecca de d ene 1 1 Starting DAGGP tate A tede ade eot ec ede dece 1 1 Installing and Starting the DOS Version of DACCF 1 2 Starting the BIOS Version of DACCF ee 1 2 When to Use DACCE eese nnne nnns 1 4 Chapter 2 Preparing the Array OVelVIGW s 1d eie eie RR EEE ASR KUBA SE ER RERRE ARIES 2 1 Selecting a Controller seen 2 2 Setting Controller Parameters for Your Application 2 3 Hardware Parameters eee 2 6 Physical Parameters

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