This site best when viewed with a modern standards-compliant browser. We recommend Firefox Get Firefox!.

Linux-HA project logo
Providing Open Source High-Availability Software for Linux and other OSes since 1999.

USA Flag UK Flag

Japanese Flag

Homepage

About Us

Contact Us

Legal Info

How To Contribute

Security Issues

This web page is no longer maintained.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:
2017-12-15 01:16:10

Quorum

Quorum is the name given to a mechanism which is intended to help solve the SplitBrain problem, by selecting no more than one ClusterPartition when failures in cluster communication cause the cluster to split into multiple ClusterPartitions.

Once a ClusterPartition is selected to have quorum, that partition can run services for the cluster.

The most well-known method of awarding quorum to a ClusterPartition for an n-node cluster for quorum is to award quorum to that partition which has more than n/2 nodes in it.

Of course, this causes problems for the case where n is 2, since any failure at all will cause the entire cluster to shut down.

To aid in this problem, there are a variety of other methods available to compute quorum, or break ties in quorum voting.

In Linux-HA, we provide a QuorumDaemon to help resolve this situation.

See Also

Split-brain, quorum, fencing overview, SplitBrain, fencing, QuorumDaemon