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  1. Core Server
  2. SERVER-9730

Asymmetrical network partition can cause the election of two PRIMARY nodes

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Details

    • Bug
    • Status: Closed
    • Critical - P2
    • Resolution: Done
    • 2.2.4, 2.4.3, 2.5.0
    • 2.2.5, 2.4.4, 2.5.1
    • Replication
    • None
    • ALL

    Description

      Consider a replica set with three nodes: A, B, C. 'A' is PRIMARY, 'B' and 'C' are SECONDARY.

      If there is a network partition between 'A' and 'C', then:

      • A is still PRIMARY because it can see a majority of the set
      • C will start an election trying to become PRIMARY
        • It can see a majority of the set
        • It cannot see a primary

      If, for whatever reason, 'B' allows 'C' to become PRIMARY, then the set will have two PRIMARY nodes until one of them is stepped down.

      Attachments

        Issue Links

          is duplicated by

          Bug - A problem which impairs or prevents the functions of the product. SERVER-8145 Two primaries for the same replica set

          • Major - P3 - Major loss of function.
          • Closed
          is related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-9756 network partition where minority was primary and stayed primary

          • Major - P3 - Major loss of function.
          • Closed
          related to

          Bug - A problem which impairs or prevents the functions of the product. SERVER-9283 lastHeartbeatRecv flaps between invalid and valid dates

          • Major - P3 - Major loss of function.
          • Closed

          Activity

            People

              milkie@mongodb.com Eric Milkie
              william.zola@10gen.com William Zola
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              Dates

                Created:
                Updated:
                Resolved: