A heartbeat in Sun Cluster Geographic Edition is a container for a collection of heartbeat plug-ins. A heartbeat has a name and one property that you can tune, Query_interval. The Query_interval property specifies the delay between heartbeat status requests.
The heartbeat plug-in facilitates the actual physical monitoring activity. The plug-in is defined by a required query command or query library, an optional requester and responder agent, a type, and a Plugin_properties string.
The Sun Cluster Geographic Edition product provides the following default plug-ins:
tcp_udp_plugin — Performs a simple heartbeat check on the cluster logical host IP address. If tcp_udp_plugin cannot use UDP port 2084, the plug-in tries to use TCP port 2084.
The Internet Assigned Numbers Authority (IANA) has officially assigned port number 2084 for use by the Sun Cluster Geographic Edition heartbeats.
ping_plugin — Pings the cluster logical hostname on the remote cluster.
A default heartbeat that uses the default heartbeat plug-ins is created every time you run geops create or geops join without specifying a custom heartbeat. The name of the default heartbeat is hb_localclustername~remoteclustername. For more information about the geops command, refer to the geops(1M) man page.
You can create custom heartbeat plug-ins and associate them with existing default heartbeats or with new custom heartbeats.
Custom heartbeats are provided for special circumstances and require careful configuration. Consult your Sun specialist for assistance if your system requires the use of custom heartbeats.
If you create a custom heartbeat, you must add at least one plug-in to prevent the partnership from remaining in degraded mode.