Uploaded image for project: 'JBoss Enterprise Application Platform'
  1. JBoss Enterprise Application Platform
  2. JBEAP-20956

Messaging Documentation Missing Warning About Quorum Size and Presents Incorrect Examples for Replicated HA Configuration

    XMLWordPrintable

Details

    • 3

    Description

      The AMQ-7 mainline documentation contains this critical warning about configuring replicated HA:

      Replication requires at least three live-backup pairs to lessen (but not eliminate) the risk of network isolation. Using at least three live-backup broker pairs enables your cluster to use quorum voting to avoid having two live brokers.
      

      This warning is missing from the JBoss EAP 7.0-7.3 documentation and the documentation presents examples of replicated / replicated-colocated messaging consisting of 2 live/backup pairs.

      Configuring replication with fewer than 3 live / 3 backup nodes dramatically increases the risk of a split brain scenario (with potential for corruption / message loss), as replication relies on quorum voting to make a go-live determination when a master appears to be unavailable. Since quorum-size effectively equals cluster size with fewer than 3 nodes, quorum voting is ineffective with fewer than 3 lives (no majority available in the absence of a single live node).

      Attachments

        Issue Links

          Activity

            People

              bobjohns@redhat.com Robert Johnson (Inactive)
              bobjohns@redhat.com Robert Johnson (Inactive)
              Votes:
              0 Vote for this issue
              Watchers:
              2 Start watching this issue

              Dates

                Created:
                Updated:
                Resolved: