Controlling Clean Behavior on Resource Faults

The ManageFaults attribute specifies whether VCS calls the Clean entry point when a resource faults. ManageFaults is a service group attribute; you can configure each service group to operate as desired.

• If the ManageFaults attribute is set to ALL, VCS calls the Clean entry point when a resource faults.
• If the ManageFaults attribute is set to NONE, VCS takes no action on a resource fault; it "hangs" the service group until administrative action can be taken. VCS marks the resource state as ADMIN_WAIT and does not fail over the service group until the resource fault is removed and the ADMIN_WAIT state is cleared.

VCS calls the resadminwait trigger when a resource enters the ADMIN_WAIT state due to a resource fault if the ManageFaults attribute is set to NONE. You can customize this trigger to provide notification about the fault. See resadminwait Event Trigger for more information.

Controlling Fault Propagation

The FaultPropagation attribute defines whether a resource fault is propagated up the resource dependency tree. It also defines whether a resource fault causes a service group failover.

• If the FaultPropagation attribute is set to 1 (default), a resource fault is propagated up the dependency tree. If a resource in the path is critical, the service group is taken offline and failed over, provided the AutoFailOver attribute is set to 1.
• If the FaultPropagation is set to 0, resource faults are contained at the resource level. VCS does not take the dependency tree offline, thus preventing failover. If the resources in the service group remain online, the service group remains in the PARTIAL|FAULTED state. If all resources are offline or faulted, the service group remains in the OFFLINE| FAULTED state.

When a resource faults, VCS fires the resfault trigger and sends an SNMP trap. The trigger is called on the system where the resource faulted and includes the name of the faulted resource. See resfault Event Trigger for more information.

Customized Behavior Diagrams

The illustrations in this section depict how the ManageFaults and FaultPropagation attributes change VCS behavior when handling resource faults The following illustration depicts the legends used in the section.

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Scenario: Resource with a critical parent and ManageFaults=NONE

The service group in the following example has five resources. The ManageFaults attribute is set to NONE for resource R2.

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If resource R2 fails, the resource is marked as ONLINE|ADMIN_WAIT. The Clean entry point is not called for the resource. VCS does not take any other resource offline.

Scenario: Resource with a critical parent and FaultPropagation=0

In the following example, the FaultPropagation attribute is set to 0.

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When resource R2 faults, the Clean entry point is called and the resource is marked as faulted. The fault is not propagated up the tree, and the group is not taken offline.