Configurable Windows Cluster Heartbeat

An update is available that adds a file share witness feature and a configurable cluster heartbeats feature to Windows Server 2003 Service Pack 1-based server clusters

Configurable cluster heartbeats

The configurable cluster heartbeats feature enables you to configure cluster heartbeat parameters. This may help avoid unnecessary cluster failovers. These failovers occur because of a temporary network problem that may cause packets to be dropped or delayed. The configurable cluster heartbeats feature may help in an environment where cluster nodes are geographically dispersed.

The current cluster heartbeat algorithm sends a heartbeat message every 1.2 seconds from each interface on each cluster node. This message is sent to each interface on the same cluster network. Therefore, each cluster node both sends a heartbeat message every 1.2 seconds and expects to receive a heartbeat message every 1.2 seconds. If two consecutive heartbeats from the same interface are missed, the Cluster service suspects that an interface failure may have occurred. If six consecutive heartbeats are missed from all the interfaces on a node, the Cluster service suspects that a node failure may have occurred.

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