On each cluster system, the clumembd daemon issues heartbeats (pings) across the point-to-point Ethernet lines to which the cluster members are connected.
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You can enable both broadcast heartbeating and multicast heartbeating, but at least one of these features must be used. Multicast heartbeating over a channel-bonded Ethernet interface provides good fault tolerance and is recomended over broadcast heartbeating over a backup crossover cable connection. |
You can specify the following properties for the clumembd daemon:
Log Level — Determines the level of event messages that get logged to the cluster log file (by default /var/log/messages). Choose the appropriate logging level from the menu.
Failover Speed—Determines the number of seconds that the cluster service waits before shutting down a nonresponding member (that is, a member from which no heartbeat is detected). To set the failover speed, drag the slider bar. The default failover speed is 10 seconds.
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Decreasing failover speed increases the likelihood of false shutdowns. |
Heartbeating — Enable Broadcast Heartbeating or Enable Multicast Heartbeating by clicking the corresponding radio button. Broadcast heartbeating specifies that the broadcast IP address is to be used by the clumembd daemon when emitting heartbeats. Enable this feature when using a crossover Ethernet cable in the cluster as a backup heartbeat connection.
By default, the clumembd is configured to emit heartbeats via multicast. Multicast uses the network interface associated with the member's hostname for transmission of heartbeats.
Multicast IP Address — Specifies the IP address to be used by the clumembd daemon over the multicast channel. This field is not editable if Enable Broadcast Heartbeating is checked. The default multicast IP address used by the cluster is 225.0.0.11.