4.6. Configuring a Failover Domain

4.6. Configuring a Failover Domain

A failover domain is a named subset of cluster nodes that are eligible to run a cluster service in the event of a node failure. A failover domain can have the following characteristics:

Note

Changing a failover domain configuration has no effect on currently running services.

Note

Failover domains are not required for operation.

By default, failover domains are unrestricted and unordered.

In a cluster with several members, using a restricted failover domain can minimize the work to set up the cluster to run a cluster service (such as httpd), which requires you to set up the configuration identically on all members that run the cluster service). Instead of setting up the entire cluster to run the cluster service, you must set up only the members in the restricted failover domain that you associate with the cluster service.

Tip

To configure a preferred member, you can create an unrestricted failover domain comprising only one cluster member. Doing that causes a cluster service to run on that cluster member primarily (the preferred member), but allows the cluster service to fail over to any of the other members.

The following sections describe adding a failover domain, removing a failover domain, and removing members from a failover domain:


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