Cluster Daemons

The cluster daemons are as follows:

• Quorum daemon

  On each cluster system, the cluquorumd quorum daemon periodically writes a timestamp and system status to a specific area on the primary and backup quorum disk partitions. The daemon also reads the other cluster system's timestamp and system status information from the primary quorum partition or, if the primary partition is corrupted, from the backup partition.

• Heartbeat daemon

  On each cluster system, the cluhbd heartbeat daemon issues pings across the point-to-point Ethernet and serial lines to which both cluster systems are connected.

• Power daemon

  On each cluster system, the clupowerd power daemon monitors the remote power switch connection, if any. You will notice that there are two separate clupowerd processes running. One is the master process which responds to message requests (e.g. status and power cycle); the other process does periodic polling of the power switch status.

• Service manager daemon

  On each cluster system, the clusvcmgrd service manager daemon responds to changes in cluster membership by stopping and starting services. You may notice, at times, that there may be more than one clusvcmgrd process running. This occurs due to the fact that clusvcmgrd spawns separate processes for start, stop, and monitoring operations.

• System monitoring daemon

  On each cluster system, the clumibd and xmproxyd daemons respond to cluster monitoring requests. The Red Hat Cluster Manager GUI is the principal user of these services.