Oracle® Solaris Cluster Geographic Edition System Administration Guide

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Updated: July 2014, E39667-01

Tuning the Heartbeat Properties

Default heartbeats are created as part of partnership creation. If you use a custom heartbeat, the custom heartbeat should be created before you create a partnership. You can modify the properties of the default and custom heartbeats by using the geohb set-prop command. For more information about this command, refer to the geohb (1M) man page.

Note -  Custom heartbeats are provided for special circumstances and require careful configuration. Consult your Oracle specialist for assistance if your system requires the use of custom heartbeats.

If you modify the default value of the Query_interval property, ensure that the interval is sufficiently long. An interval that is too short causes a timeout and heartbeat-loss event before the logical hostname resource is available. This failover should result in no more than two unanswered heartbeat requests. Setting a default Query_interval value of 120 seconds with the default heartbeat.retries parameter of 3 enables the peer cluster to be unresponsive for 6 minutes (120 * 3 ) without having a false failure declared.

The heartbeat.retries parameter is specified in the com.sun.cluster.agent.geocontrol.xml file.

If you adjust the delay setting of the Query_interval property, ensure that the following condition is met:

Query_interval > worst-case-logical-host-failover-time / 2

You must empirically determine the logical-host failover time for the cluster in question.

The following must be true to avoid false failures:

Query_interval > worst-case-logical-host-failover-time / 3

You should not change the heartbeat.retries value. If you want to change the default value of the heartbeat.retries property, contact an Oracle service representative.