____________________________________________________ POLYCENTER Striping for OpenVMS VAX Release Notes These release notes provide supplementary information for the POLYCENTER Striping for OpenVMS VAX software. Disk striping converts individual disk I/O requests into multiple disk I/O requests that are then processed concurrently on multiple disk drives. This results in an increased data rate and a reduction in the effective seek time. Software Version: Version 2.1 Digital Equipment Corporation Maynard, Massachusetts ________________________________________________________________ September, 1993 The information in this document is subject to change without notice and should not be construed as a commitment by Digital Equipment Corporation. Digital Equipment Corporation assumes no responsibility for any errors that may appear in this document. Any software described in this document is furnished under a license and may be used or copied only in accordance with the terms of such license. No responsibility is assumed for the use or reliability of software or equipment that is not supplied by Digital Equipment Corporation or its affiliated companies. Restricted Rights: Use, duplication, or disclosure by the U.S. Government is subject to restrictions as set forth in subparagraph (c) (1) (ii) of the Rights in Technical Data and Computer Software clause at DFARS 252.227-7013. FCC Notice: The Equipment described in this manual generates, uses, and may emit radio frequency energy. The equipment has been type tested and found to comply with the limits for a Class A computing device pursuant to Subpart J of Part 15 of FCC Rules, which are designed to provide reasonable protection against such radio frequency interference when operated in a commercial environment. Operation of this equipment in a residential area may cause interference, in which case the user at his own expense may be required to take measures to correct the interference. © Digital Equipment Corporation 1993. All rights reserved. Printed in U.S.A. HSC, KDA, KDB, KDM, MASSBUS, MSCP, OpenVMS, RA70, RA90, RQDX3, UDA, UNIBUS, VAX Volume Shadowing, VAX, VAXcluster, VAXsimPLUS, VMS, digital, and the DIGITAL logo are trademarks of Digital Equipment Corporation. This document was prepared using VAX DOCUMENT, Version 2.1. _________________________________________________________________ Contents 1 Introduction.................................. 1 1.1 Intended Audience......................... 1 1.2 Related Documentation..................... 1 1.3 Prerequisite Software..................... 1 2 New and Changed Features...................... 2 3 Restrictions.................................. 4 4 Performance Issue with HSC K.scsi Software.... 6 5 Installation Notes............................ 8 6 Cluster Installation Notes.................... 10 Examples 1 Sample Installation....................... 8 iii 1 Introduction The POLYCENTER Striping for OpenVMS VAX Release Notes provide information for this release that is too new to be included in the POLYCENTER Striping for OpenVMS VAX Guide to Operations. These release notes are not intended to replace the existing documentation, so read them first before referring to the POLYCENTER Striping for OpenVMS VAX Guide to Operations. 1.1 Intended Audience These release notes are intended for system administrators or POLYCENTER Striping for OpenVMS VAX, Version 2.1 software users. 1.2 Related Documentation Order numbers for the following documents can be obtained from your Digital Sales Representative: o POLYCENTER Striping for OpenVMS VAX Guide to Operations o POLYCENTER Performance Adviser User's Guide o OpenVMS License Utility Manual o OpenVMS System Management Utilities: Essentials o VAX Volume Shadowing for OpenVMS o VMScluster Systems for OpenVMS 1.3 Prerequisite Software POLYCENTER Striping for OpenVMS VAX, Version 2.1 software runs on VMS Version 5.4 to OpenVMS Version 6.0. 1 2 New and Changed Features The following are new and changed features for the POLYCENTER Striping for OpenVMS VAX, Version 2.1 software: o Added capability to run on OpenVMS Version 6.0 o Added STRIPE MODIFY command o Removed /NOSYSTEM qualifier from BIND command o Served stripesets are not supported _______________________ Caution _______________________ Removing the /NOSYSTEM qualifier requires changing the backup procedures for shadowset members that are no longer stripeset members. The shadowset members must then be mounted with the following commands: $ $ ! Remove members from shadowsets $ $ DISMOUNT/NOUNLOAD $1$DUA1 $ DISMOUNT/NOUNLOAD $1$DUA2 $ $ ! Modify the member volume ids so they are unique $ $ STRIPE MODIFY/OVERRIDE_CHECK $1$DUA1, $1$DUA2 LABEL1, LABEL2 $ SET VOLUME/LABEL=LABEL1 $1$DUA1 $ SET VOLUME/LABEL=LABEL2 $1$DUA2 $ DISMOUNT/NOUNLOAD $1$DUA1 $ DISMOUNT/NOUNLOAD $1$DUA2 $ $ ! Bind and mount the members with unique stripeset device $ ! name. Use the original volume label for the stripeset device. $ $ STRIPE BIND $1$DUA1, $1$DUA2/DEVICE=STA9995 $ MOUNT STA9995 STRIPE3 $ $ ! Backup the STA9995 device. $ $ ! Dismount, unbind the stripeset and mount shadowset members back $ $ DISMOUNT STA9995 2 $ STRIPE UNBIND STA9995 $ MOUNT/SYSTEM DSA1/SHADOW=$1$DUA1 ST1 $ MOUNT/SYSTEM DSA2/SHADOW=$1$DUA2 ST2 ______________________________________________________ 3 3 Restrictions With POLYCENTER Striping for OpenVMS VAX, Version 2.1 software, "served stripesets" are no longer supported. In order to achieve the same functionality, individual disks must be served and locally bound into a stripeset at each node that wishes access to this type of stripeset. This requires that all nodes needing stripeset access to be licensed to run POLYCENTER Striping for OpenVMS VAX, Version 2.1 software. For those customers who are licensed for a previous version of POLYCENTER Striping (VAX Disk Striping Driver, Versions 2.0, 2.0A, or 2.0B) and who are using the "served stripeset" feature on a single node within a VAXcluster configuration, Digital will allow those customers to run POLYCENTER Striping for OpenVMS VAX, Version 2.1 software on all nodes within the VAXcluster without additional cost. This is a unique license grant for this specific product only and allows customers to continue to run Striping in the same manner as prior to Version 2.1 software. To convert stripesets from served stripesets to stripesets that serve the members, perform the following procedure: 1. Make sure VAXcluster nodes have direct access to the stripeset members. Section 2.2 of the POLYCENTER Striping for OpenVMS VAX Guide to Operations, The VAXcluster Environment, explains how to MSCP serve stripeset members. 2. Install POLYCENTER Striping for OpenVMS VAX, Version 2.1 software on all nodes that use the stripesets. 3. Modify the SYS$MANAGER:SYSTARTUP_VMS.COM procedure so that it executes SYS$STARTUP:STRIPE$STARTUP.COM on all nodes. 4. Modify your startup command procedure so that it executes STRIPE BIND and MOUNT commands for your stripesets on all nodes. 5. Remove the /ALLOCATION qualifier from the STRIPE BIND command. 6. Modify any MOUNT commands or logicals that refer to the striping device name so that the stripe device name does not include the allocation class. 4 7. Reboot to load the new driver and to remove any $x$STAxxx devices. 5 4 Performance Issue with HSC K.scsi Software Issue: There is a probable performance issue with HSC K.scsi software Version 8.1 and POLYCENTER Striping for OpenVMS VAX (all versions) that may result in degraded performance. Problem Description: The HSC K.scsi data channel card with software Version 8.0 and higher identifies all SCSI disks as having a track size of four sectors per track. The OpenVMS DUDRIVER records this track size in the OpenVMS I/O database (UCB$B_SECTORS). Consequently, the SHOW DEVICE/FULL and GETDVI commands return this track size. The STRIPE INITIALIZE command of the POLYCENTER Striping for OpenVMS VAX uses the track size from the OpenVMS I/O database to compute a default chunk size. Unless you specify the chunk size using the /CHUNK_SIZE qualifier, a stripeset initialized from disks connected to the HSC K.scsi data channel cards will have a chunk size of four and that will result in degraded stripeset performance. Recommendation: If you have a stripeset whose member disks are connected to an HSC K.scsi channel card, check the stripeset's chunk size by entering the following command: $ STRIPE LIST STA5: where STA5 is the name of the stripeset virtual device. If the chunk size reported is four, Digital recommends that you do the following: 1. Perform an image backup of the files on the stripeset. 2. Initialize the stripeset with a larger chunk size (as described in the next section). 3. Restore the backup to the new stripeset. 6 If you are about to build a stripeset whose member disks are connected to HSC K.scsi channel cards, then Digital recommends that you do the following: 1. Find the track size from the hardware documentation supplied with the member disks. Do not use the SHOW DEVICE/FULL command to determine the member disk track size since it will not show the correct size. 2. Compute a chunk size using the following equation: CS = Ceiling[15*(MEAN_IO_SIZE-1)/TRACK_SIZE]*TRACK_SIZE If you do not know the mean I/O size, use 8. 3. Initialize your stripeset by entering the following command: $ STRIPE INITIALIZE/CHUNK_SIZE=CS. Do not use the default chunk size supplied by the STRIPE INITIALIZE command, as it may not be correct. The equation in step 2 assumes that the average transfer size is below 128 sectors. If your average transfer size is above 128 sectors, Digital recommends that you contact a Digital software support specialist for advice concerning the optimum chunk size. If you find that the member disks have a variable track size, as in zone-bit-recording, Digital recommends that you use the disk's largest track size when computing chunk size. The STRIPE INITIALIZE command in Version 2.1 of POLYCENTER Striping for OpenVMS VAX software will improve the formula used to compute default chunk size. However, as long as the track size in the VMS I/O database does not match the physical disk, you will be able to select a better value using the above procedures. 7 5 Installation Notes Before attempting installation, refer to Section 3 of these Release Notes. The following is an example of an installation for Striping: Example 1 Sample Installation $ @SYS$UPDATE:VMSINSTAL VAX/VMS Software Product Installation Procedure V5.4 It is 1-AUG-1993 at 09:18. Enter a question mark (?) at any time for help. Are you satisfied with the backup of your system disk [YES]? YES Where will the distribution volumes be mounted: MUA0: Enter the products to be processed from the first distribution volume set. Products: stripe021 Enter installation options you wish to use (none): The following products will be processed: STRIPE V2.1 Beginning installation of STRIPE V2.1 at 09:51 %VMSINSTAL-I-RESTORE, Restoring product save set A ... %VMSINSTAL-I-RELMOVED, Product's release notes have been moved to SYS$HELP. Do you want to purge files replaced by this installation [YES]? YES Building the striping driver %STRIPE-I-VMSVER, Assembling STDRIVER for VMS version 5+ To add the striping driver startup procedure to the system startup procedure, place the following command in your STARTUP.COM file. @SYS$STARTUP:STRIPE$STARTUP.COM Be sure to read the documentation concerning STRIPE$SYSTARTUP.COM in the POLYCENTER Striping for OpenVMS VAX Guide to Operations. The primary installation phase has completed. Be sure to read the release notes, and note especially that you may need to adjust the SYSBOOT (SYSGEN) parameters which control the amount of nonpaged pool, and number of SPTs for STRIPE to work. (continued on next page) 8 Example 1 (Cont.) Sample Installation A test package to verify that the POLYCENTER Striping for OpenVMS VAX software works correctly has been placed on SYS$TEST: and may be run with the following command: $ @SYS$TEST:STRIPE$TEST WARNING!! WARNING!! WARNING!! WARNING!! This test requires the use of two disks. Data on the disks used in this test will be destroyed!!!!! Any V1.0 stripe sets will need to be backed up, stripe initialized, stripe bound, VMS initialized, mounted, and restored to take advantage of the new features. %VMSINSTAL-I-MOVEFILES, Files will now be moved to their target directories... Installation of STRIPE V2.1 completed at 09:54 Enter the products to be processed from the next distribution volume set. Products: VMSINSTAL procedure done at 09:55 9 6 Cluster Installation Notes Once the kit is installed on one node, finish the installation for the other nodes in the cluster by entering the following commands: $ SYS$STARTUP:STRIPE$STARTUP.COM $ INSTALL/REPLACE SYS$COMMON[SYSLIB]:DCLTABLES.EXE/OPEN/SHAR/LINK $ INSTALL/REPLACE SYS$COMMON[SYSMSG]:STRIPEMSGFIL.EXE/OPEN/SHAR 10