heartbeat

The Heartbeat Subsystem for High-Availability Linux

heartbeat is a sophisticated multinode resource manager for High Availability clusters. It can failover arbitrary resources, ranging from IP addresses over NFS to databases that are tied in via resource scripts. The resources can have arbitrary dependencies for ordering or placement between them. heartbeat contains a cluster membership layer, fencing, and local and clusterwide resource management functionality. 1.2/1.0 based 2-node only configurations are supported in a legacy mode. heartbeat implements the following kinds of heartbeats: - Serial ports - UDP/IPv4 broadcast, multi-cast, and unicast - IPv4 "ping" pseudo-cluster members.