Upgrade do's and don'ts

This section lists the major tasks to do during or before an upgrade, and it also lists what not to do.

Upgrade do's

Make sure you verify the following:

  • Take a cluster snapshot and save it to the /tmp directory as well as to another machine and CD.
  • Save a copy of any event script files to the /tmp directory as well as to another machine and CD.
  • Ensure that the same level of cluster software (including PTFs) are on all nodes before beginning a migration.
  • Ensure that the cluster software is committed (and not just applied).
  • Run cluster verification and make sure no errors are reported. Then you will know your configuration is in a working state before you start the upgrade.
  • During migration from one version of PowerHA® SystemMirror® to another version you can start and stop cluster services but you cannot use the manual option when starting cluster services. Manual startup is disabled when migration begins and cannot be used again until the migration is completed.
    Note: In a parent and child resource group configuration with different home nodes, if you start cluster services on the node where the parent resource group is in an unmanaged state the corresponding child resource group is not released and reacquired.

Upgrade don'ts

During any type of upgrade, do not do the following tasks:

  • Do not save your cluster configuration or customized event scripts under these directory paths: /usr/es/sbin/cluster or /usr/lpp/cluster. Data in these directories might be lost during an upgrade. Instead, copy files to a separate system or to a CD.
  • Do not verify and synchronize the cluster configuration.
  • Do not attempt a dynamic automatic reconfiguration (DARE). For example, do not change node priority in a resource group, add or remove a network, update an LVM component, or add users to a cluster.
  • Do not use mixed versions of the cluster software for an extended period of time (hybrid state).

When migrating an active cluster, one node at a time (a rolling migration), the use of commands and functions are restricted as follows when the cluster has mixed versions (that is, it is in a hybrid state):

  • Do not change the cluster topology or configuration.
  • Do not run the clRGmove command from the command line or the SMIT interface to move resource groups during a migration.
  • Do not use any System Management (C-SPOC) functions except to start or stop cluster services, or to move a resource group.
  • Do not use the Problem Determination Tools > View Current State function.
  • Do not use the Cluster Nodes and Networks > Manage the Cluster > Snapshot Configuration option or run the clsnapshot command.
  • Do not use the Problem Determination Tools > Recover From PowerHA SystemMirror Script Failure option, or run the clruncmd command, except when running the command or SMIT option from the target node specified by the command.