wiki:ServiceOperationalBehaviors
Last modified 3 years ago Last modified on 05/22/11 17:24:21

These are default behaviors when using classic mode and out-of-the-box central_processing mode. These operations apply to both services and virtual machines, except for the migrate operation, which only works with virtual machines.

Service Operations

  • enable - start the service, optionally on a preferred target and optionally according to failover domain rules. In absence of either, the local host where clusvcadm is run will start the service. If the original start fails, the service behaves as though a relocate operation was requested (see below). If the operation succeeds, the service is placed in the started state.
  • disable - stop the service and place into the disabled state. This is the only permissible operation when a service is in the failed state.
  • relocate - move the service to another node. Optionally, the administrator may specify a preferred node to receive the service, but the inability for the service to run on that host (e.g. if the service fails to start or the host is offline) does not prevent relocation, and another node is chosen. Rgmanager attempts to start the service on every permissible node in the cluster. If no permissible target node in the cluster successfully starts the service, the relocation fails and the service is attempted to be restarted on the original owner. If the original owner can not restart the service, the service is placed in the stopped state.
  • stop - stop the service and place into the stopped state.
  • migrate - migrate the virtual machine to another node. The administrator must specify a target node. Depending on the failure, a failure to migrate may result with the virtual machine in the failed state or in the started state on the original owner.
  • convalesce - restart any stopped non-critical subtrees of the given service.

There are also two specific operations and behaviors noted on the ServiceFreeze page.

Service States

  • disabled - The service will remain in the disabled state until either an administrator re-enables the service or the cluster loses quorum (at which point, the autostart parameter is evaluated). An administrator may enable the service from this state.
  • failed - The service is presumed dead. This state occurs whenever a resource's stop operation fails. Administrator must verify that there are no allocated resources (mounted file systems, etc.) prior to issuing a disable request. The only action which can take place from this state is disable.
  • stopped - When in the stopped state, the service will be evaluated for starting after the next service or node transition. This is a very temporary measure. An administrator may disable or enable the service from this state.
  • recovering - The cluster is trying to recover the service. An administrator may disable the service to prevent recovery if desired.
  • started - If a service status check fails, recover it according to the service recovery policy. If the host running the service fails, recover it following failover domain & exclusive service rules. An administrator may relocate, stop, disable, and (with virtual machines) migrate the service from this state. Services with failed non-critical subtrees will also have a P flag ("partial").

Note: Other states (starting, stopping, ...) are special cases of the started state.