HP OpenVMS 8.x manual Preparing Your System for a Rolling Upgrade

the remaining OpenVMS Cluster members. Make sure the target system disk is not mounted on any other node in the cluster and remains dismounted during the upgrade. It should be mounted only on the system that is performing the upgrade. (For information about dismounting disks, see Section 5.5.2.3 (page 91).)

NOTE: Any attempt to access the target system disk from the remaining OpenVMS Cluster members will corrupt the target disk. Even if the target system disk is mounted only by a remaining cluster member and no file access is performed, the target disk will probably be corrupted. If a disk is corrupted in this way, the only supported recovery is to restore the backup copy of the corrupted disk.

•HP recommends that all Alpha computers in a cluster run the same (preferably the latest) version of the OpenVMS Alpha operating system, and that all Integrity servers run the same version of the OpenVMS I64 operating system.

•You cannot perform a rolling upgrade if all systems boot from a single system disk. Perform a concurrent upgrade instead.

•The upgrade procedure affects the queuing system as follows:

—The queuing system is not active on the system you are upgrading; do not attempt to execute a START/QUEUE/MANAGER command.

—You cannot create a queue database on the operating system CD/DVD (because it is not writable).

—The queue manager process on other nodes in the cluster can continue to run during the upgrade if the queue database is not on the disk being upgraded.

5.5.2.3Preparing Your System for a Rolling Upgrade

To prepare for a rolling upgrade, follow these steps:

1.Log in to any node where the target disk is mounted as a data disk rather than as the system disk. (That disk must be the one on which you already performed the preupgrade tasks described in Chapter 4 (page 77).)

2.Check the votes and make adjustments to maintain the proper quorum so the cluster can continue to operate throughout the upgrade. (HP OpenVMS Cluster Systems describes this procedure in detail.)

3.Use the DCL command DISMOUNT/CLUSTER to dismount the data disk. (You can also perform this operation using the SYSMAN utility.)

Note that you can ignore messages from nodes where the specified data disk is being used as the system disk.

4.Verify that the data disk has been dismounted successfully by entering the following commands:

$ MCR SYSMAN

SYSMAN> SET ENVIRONMENT/CLUSTER SYSMAN> DO SHOW DEVICE disk-name

Examine the display to be sure the disk is not mounted on any nodes as a data disk. Noting the value listed in the Trans Count field can help you make that determination: A value of less than 50 indicates that the disk is mounted as a data disk rather than as the system disk; a much larger value (for example, 300) indicates that the disk most likely is the system disk.

5.If the disk is still mounted on any nodes as a data disk, use the SYSMAN utility to dismount the disk; otherwise, exit the SYSMAN utility.

5.5 Types of Upgrades 91