NOTE: Using the min_package_node policy, when node 2 is repaired and brought back into the cluster, it will then be running the fewest packages, and thus will become the new standby node.

If these packages had been set up using the configured_node failover policy, they would start initially as in Figure 16, but the failure of node 2 would cause the package to start on node 3, as in Figure 18:

Figure 18 CONFIGURED_NODE Policy Packages after Failover

If you use configured_node as the failover policy, the package will start up on the highest priority node in the node list, assuming that the node is running as a member of the cluster. When a failover occurs, the package will move to the next highest priority node in the list that is available.

Failback Policy

The use of the failback_policy parameter allows you to decide whether a package will return to its primary node if the primary node becomes available and the package is not currently running on the primary node. The configured primary node is the first node listed in the package’s node list.

The two possible values for this policy are automatic and manual. The parameter is set in the package configuration file:

As an example, consider the following four-node configuration, in which failover_policy is set to configured_node and failback_policy is automatic:

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HP Serviceguard manual Configurednode Policy Packages after Failover, Failback Policy