Automatic Actions for Service Group Dependencies

Automatic Online

If a service group is configured to start automatically on a system, it is brought online only if the group's dependency requirements are met. This implies that in an online local dependency, parent groups are brought online only after all child groups are brought online.

AutoRestart

If a persistent resource on a service group (GROUP_1 in this example) faults, the service group is automatically failed over to another system in the cluster under the following conditions:

• The AutoFailOver attribute is set.
• There is another system in the cluster to which GROUP_1 can fail over.

If neither of the above conditions is met (the AutoFailOver attribute is not set or other systems in the cluster are unavailable), GROUP_1 remains offline and faulted, even after the faulted resource becomes online.

Setting the AutoRestart attribute enables a service group to be brought back online without manual intervention. In the above example, setting the AutoRestart attribute for GROUP_1 would enable VCS to bring the group back online, after the resource came online on the system where the resource faulted.

Or, if GROUP_1 could not fail over to another system because none was available, setting the AutoRestart attribute would enable VCS to bring the group back online on the first available system after the group's faulted resource came online on that system.

For example, NIC is a persistent resource. In some cases, when a system boots and VCS starts, VCS probes all resources on the system. It is possible that when VCS probes the NIC resource, the resource may not yet be online because the networking is not up and fully operational. When this occurs, VCS will mark the NIC resource as faulted, and will not bring the service group online. However, when the NIC resource becomes online and if AutoRestart is enabled, the service group is brought online.