Changing the Cluster Quorum Configuration RRS feed

  • Question

  • I had a two node 2008 R2 Cluster and i added a third node and it was recommended to change the quorum configuration from "Node and Disk Majority" to just "Node Majority".  When i make this change will the cluster go down?

    i have services and sql applications running in this cluster and i don't want them to be affected by this change.

    Also, with this Node Majority model what should i make sure gets backed up in order to be able to restore the cluster in case of failure?


    Thursday, June 30, 2011 4:00 PM


All replies

  • no, the cluste will not go down.  Changing the quorum requires all nodes to be available, so the cluster will be up.
    Thursday, June 30, 2011 4:15 PM
  • A two node cluster should have a witness disk and be set to "Node and Disk Majority".  If you go with "Node Majority" the cluster will fail when one node is offline.  With "Node and Disk Majority" the cluster can survive with any two of the three elements working. 

    The Cluster Quorum model can be changed without taking the cluster down as long as the "before" and "after" configurations would result in an online cluster.

    Geoff N. Hiten Principal Consultant Microsoft SQL Server MVP
    Thursday, June 30, 2011 8:48 PM
  • Yes, you can change the clusters quorum model on the fly with zero downtime while the cluster is up and running in production.

    See this doc for more information about the various quorum modes:


    Friday, July 1, 2011 3:17 AM