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This web page is no longer maintained. Information presented here exists only to avoid breaking historical links.
The Project stays maintained, and lives on: see the Linux-HA Reference Documentation.
To get rid of this notice, you may want to browse the old wiki instead.

1 February 2010 Hearbeat 3.0.2 released see the Release Notes

18 January 2009 Pacemaker 1.0.7 released see the Release Notes

16 November 2009 LINBIT new Heartbeat Steward see the Announcement

Last site update:
2019-12-12 23:32:03

ucast - configures unicast Heartbeat communication

The ucast directive configures Heartbeat to communicate over a UDP unicast communications link. The udpport directive is used to configure which port is used for these unicast communications if the udpport directive is specified before the ucast directive, otherwise the default port will be used.

The general syntax of a ucast directive is:

ucast dev peer-ip-address

Where dev is the device to use when talking to the peer, and peer-ip-address is the IP address we will send packets to.

Although this is a unicast communication link, the UDP packets sent over this link is a multicast protocol.

A sample ucast directive is shown below:

ucast eth0

This directive will cause us to send packets to over interface eth0.

Note that ucast directives which go to the local machine are effectively ignored. This allows the directives on all machines to be identical.