Resource group behavior during cluster events
Look here for an overview of resource group events and describe when PowerHA® SystemMirror® moves resource groups in the cluster, how the resource groups are placed on the nodes, and how to identify the causes of the underlying cluster events.
This information may be especially useful for experienced PowerHA SystemMirror users who are familiar with previous resource group handling by PowerHA SystemMirror but may not be aware of changes made in recent releases.
It is assumed that the reader is familiar with basic resource group fallover policies.
Once you have planned and defined the cluster topology and resources, PowerHA SystemMirror monitors the working cluster and takes actions to recover when failures are detected. PowerHA SystemMirror monitors resources and launches events to handle resource groups. You do not need to specify these actions in the cluster; they are initiated automatically.
PowerHA SystemMirror manages resource groups by:
- Moving only the resource groups that are affected by a failure of an individual resource to another node in the cluster.
- Taking recovery actions when it fails to acquire resource groups on a node. This can happen when PowerHA SystemMirror attempts to move a resource group to another node in the cluster, but fails to acquire it on that node. You can disable automatic recovery, if needed.