Upgrading the OperatingSystem on a System Disk Shadow Set
It is important to upgrade the operating system at a timewhen your system can afford to have its shadowing support disabled.This is because you cannot upgrade to new versionsof the OpenVMS operating system on a shadowed system disk. If youattempt to upgrade a system disk while it is an active member ofa shadow set, the upgrade procedure will fail.
Procedurefor Upgrading Your Operating System This procedure is divided into four parts:
Preparing a shadowed systemdisk for the upgrade.
Performing the upgrade.
Enabling volume shadowingon the upgraded system.
Booting other nodes in anOpenVMS Cluster system from the upgraded disk.
Preparinga Shadowed System Disk
On OpenVMS Clustersystems, choose the node on which you want to perform the upgrade.
Create a nonshadowed system disk to do the upgradeusing either of these methods:
Use BACKUP to create a compressedcopy of the shadow set on a single scratch disk (a disk with no usefuldata). See Using BACKUP/IMAGE on a Shadow Set foran example.
Enter the MOUNT/OVERRIDE=SHADOW_MEMBERSHIP commandon the upgrade disk to zero the shadowing-specific information onthe storage control block (SCB) of the disk. Do not mount the diskfor systemwide or clusterwide access; omit the /SYSTEM and /CLUSTERqualifiers on the MOUNT command line.
Use the DCL command SET VOLUME/LABEL=volume-label device-spec [:] to change the label on the upgrade disk. (The SETVOLUME/LABEL command requires write access [W] to the index fileon the volume. If you are not the volume owner, you must have eithera system UIC or the SYSPRV privilege.) For OpenVMS Cluster systems,ensure that the volume label is a unique name across the cluster.
If you need to change the volume label of a disk thatis mounted across the cluster, be sure you change the label on allnodes in the OpenVMS Cluster system. For example, you could propagatethe volume label change to all nodes in the cluster with one SYSMANutility command, after you define the environment as the cluster:
SYSMAN> SET ENVIRONMENT/CLUSTER SYSMAN> DO SET VOLUME/LABEL=new-labeldisk-device-name:
Ensure that the boot command line or file bootsfrom the upgrade disk. The manner in which you store the boot commandinformation depends on the processor on which you are working. Formore information about storing boot commands, see the instructionsin your hardware installation guide, the upgrade and installationsupplement for your VAX computer, or the upgrade and installationmanual for your Alpha computer. If volume shadowing is enabled on the node, disable it accordingto the instructions in step 6. Otherwise, proceed to Performing the Upgrade .
Prepare to perform the upgrade procedure by disablingsystem disk shadowing (if it is enabled) on the node to be upgraded.
You cannot perform an upgrade on a shadowed system disk.If your system is set up to boot from a shadow set, you must disableshadowing the system disk before performing the upgrade. This requireschanging SYSGEN parameter values interactively using the SYSGENutility.
Invoke SYSGEN by entering the following command:
$ RUN SYS$SYSTEM:SYSGEN
On OpenVMS Alpha systems, enter the following:
SYSGEN> USE upgrade-disk:[SYSn.SYSEXE]ALPHAVMSSYS.PAR SYSGEN>
On OpenVMS VAX systems, enter the following:
SYSGEN> USE upgrade-disk:[SYSn.SYSEXE]VAXVMSSYS.PAR SYSGEN>
The USE command defines the system parameter file from whichdata is to be retrieved. You should replace the variable upgrade-disk with the name of the disk to be upgraded. For thevariable n in [SYSn.SYSEXE], use the system root directory you want toboot from (this is generally the same root you booted from beforeyou started the upgrade procedure). Disable shadowingof the system disk by setting the SYSGEN parameter SHADOW_SYS_DISKto 0, as follows:
Type EXIT or press Ctrl/Z to exit the SYSGEN utility and returnto the DCL command level. You must also change parameters in the MODPARAMS.DAT file before shuttingdown the system. Changing parameters before shutdown ensures thatthe new system parameter values take effect when AUTOGEN reads theMODPARAMS.DAT file and reboots the nodes. Edit upgrade-disk:[SYSn:SYSEXE]MODPARAMS.DAT to set SHADOWING and SHADOW_SYS_DISKto 0. Even if you plan to use the upgraded system disk to upgradethe operating system on other OpenVMS Cluster nodes, you shouldcomplete the upgrade on one node before altering parameters forother nodes. Proceed to Performing the Upgrade .
Performingthe Upgrade
Boot from andperform the upgrade on the single, nonshadowed disk. Follow theupgrade procedure described in the OpenVMS upgrade and installationmanual.
If you are upgrading a system that already has thevolume shadowing software installed and licensed, then skip to Part3. Otherwise, you must register the Volume Shadowing for OpenVMSProduct Authorization Key (PAK) or keys. PAK registration is describedin the release notes and cover letter supplied with your installation kit.
EnablingVolume Shadowing on the Upgraded System Once the upgrade is complete and the upgraded node has finishedrunning AUTOGEN, you can enable shadowing for the upgraded nodeusing the following steps.
Invoke the SystemGeneration utility (SYSGEN) by entering the following command:
$ RUN SYS$SYSTEM:SYSGEN SYSGEN> USE CURRENT SYSGEN>
The USE CURRENT command initializes the SYSGEN work area withthe source information from the current system parameter file ondisk. (To find out the current value of system parameters, use the SHOWcommand [for example, SHOW SHADOWING] to see the current systemparameter values as well as the minimum, maximum, and default valuesof the parameters.) To enable shadowing, set the system parameter SHADOWING to2. If the system disk is to be a shadow set, set the system parameterSHADOW_SYS_DISK to 1, and set the SHADOW_SYS_UNIT parameter to theunit number of the virtual unit, as follows (assume the system diskvirtual unit is DSA54):
SYSGEN> SET SHADOWING 2 SYSGEN> SET SHADOW_SYS_DISK 1 SYSGEN> SET SHADOW_SYS_UNIT 54 SYSGEN> WRITE CURRENT
Type EXIT or press Ctrl/Z to exit the SYSGEN utility and returnto the DCL command level.
To ensure that volume shadowing is enabled eachtime AUTOGEN executes, edit the SYS$SYSTEM:MODPARAMS.DAT file toset the shadowing parameters. For OpenVMS Cluster systems, set systemparameters in MODPARAMS.DAT on each node that uses volume shadowing.See Chapter 3 for more information about editing the MODPARAMS.DATfile.
Shut down the system on which you performed theupgrade, and reboot.
BootingOther Nodes in the OpenVMS Cluster System from the Upgraded Disk If other nodes boot from the upgraded disk, the OpenVMS upgradeprocedure automatically upgrades and runs AUTOGEN on each node whenit is booted. The procedure for booting other nodes from the upgraded diskdiffers based on whether the upgraded disk has been made a shadowset.
If the upgradeddisk is not yet a shadow set:
Disable shadowing(if it is enabled) for the system disk on the nodes to be upgraded.
Alter the boot files for those nodes so they bootfrom the upgraded disk.
Make sure the system parameters in the node-specificSYS$SYSTEM:MODPARAMS.DAT files are correct (as described in Setting System Parameters). When the OpenVMSupgrade procedure invokes AUTOGEN, it will use these parameter settings.
Boot the nodes from the upgraded disk.
If the upgraded disk is already a shadow set member,additional steps are required:
For eachnode to be booted from the upgraded disk, edit VAXVMSSYS.PAR forVAX systems and ALPHAVMSSYS.PAR for Alpha systems, and MODPARAMS.DATto enable system disk shadowing. Set SHADOWING to 2, SHADOW_SYS_DISKto 1, and SHADOW_SYS_UNIT to the number of the system disk's virtualunit name. Remember to modify the files on the upgraded disk, noton the system disk, prior to upgrade.
Modify the computer console so that the system bootsfrom the upgraded disk. On VAX computers, depending on which model you have, you canalter the boot file on the console media or use a console commandto change nonvolatile RAM. On Alpha computers, you can use the SET BOOTDEF_DEV consolecommand. For more information, see the hardware information or theupgrade and installation manual for your system.
Boot each node. With shadowing enabled in each node'sALPHAVMSSYS.PAR or VAXVMSSYS.PAR on the upgraded disk, the nodewill be able to boot from the shadowed (upgraded) system disk.
Once you have successfully upgraded the system or systemsand you have completed other postupgrade work (such as layered productinstallations), perform the following steps:
Mount additionalshadow set members into the shadow set, if necessary. Do not usea command procedure to add members to a system disk shadow set.For more information, see Booting from a System Disk Shadow Set.
HP Volume Shadowing for OpenVMS
Performing System Management Tasks on Shadowed... 
