After rebooting, node 1 rejoins the cluster. At that point, pkgA will be automatically stopped on node 4 and restarted on node 1.

Figure 21 Automatic Failback Configuration After Restart of Node 1

CAUTION: Setting the failback_policy to automatic can result in a package failback and application outage during a critical production period. If you are using automatic failback, you may want to wait to add the package’s primary node back into the cluster until you can allow the package to be taken out of service temporarily while it switches back to the primary node.

Serviceguard automatically chooses a primary node for a package when the NODE_NAME is set to '*'. When you set the NODE_NAME to '*' and the failback_policy is automatic, if you add, delete, or rename a node in the cluster, the primary node for the package might change resulting in the automatic failover of that package.

Using Older Package Configuration Files

If you are using package configuration files that were generated using a previous version of Serviceguard, HP recommends you use the cmmakepkg command to open a new template, and then copy the parameter values into it. In the new template, read the descriptions and defaults of the choices that did not exist when the original configuration was made. For example, the default for failover_policy is now configured_node and the default for failback_policy is now manual.

For full details of the current parameters and their default values, see Chapter 6: “Configuring Packages and Their Services ” (page 227), and the package configuration file template itself.

Using the Generic Resources Monitoring Service

Generic Resources module is a resource monitoring mechanism in Serviceguard that allows you to monitor critical resources for a package through System Fault Management (SFM), or custom monitors by configuring these monitors as user-defined services. It provides integration of custom, user-defined monitors in Serviceguard by configuring generic resources as part of package configuration. Generic resources can also be used as an alternative approach to the Event Monitoring Service Hardware Monitors. With generic resources different kind of monitoring

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HP Serviceguard manual Using Older Package Configuration Files, Using the Generic Resources Monitoring Service