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  1. Core Server
  2. SERVER-10375

DNS failures can cause a primary-less state that wouldn't exist if a node had gone down entirely

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    Details

    • Type: Bug
    • Status: Closed
    • Priority: Major - P3
    • Resolution: Gone away
    • Affects Version/s: 2.4.5
    • Fix Version/s: None
    • Component/s: Replication
    • Labels:
    • Operating System:
      ALL
    • Steps To Reproduce:
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      Build a cluster of three nodes between two servers (SECONDARY and ARBITER on one server, PRIMARY on the other)

      Remove the entries for the SECONDARY and ARBITER hosts from the PRIMARY's /etc/hosts, simulating the loss of DNS resolution for that node

      The SECONDARY and ARBITER still have /etc/hosts records for the PRIMARY (simulating that DNS still works for them)

      The PRIMARY will step down, but the SECONDARY will not run for election as the (now former) PRIMARY would veto.

      Show
      Build a cluster of three nodes between two servers (SECONDARY and ARBITER on one server, PRIMARY on the other) Remove the entries for the SECONDARY and ARBITER hosts from the PRIMARY's /etc/hosts, simulating the loss of DNS resolution for that node The SECONDARY and ARBITER still have /etc/hosts records for the PRIMARY (simulating that DNS still works for them) The PRIMARY will step down, but the SECONDARY will not run for election as the (now former) PRIMARY would veto.

      Description

      If you end up with a one-way DNS partition, the PRIMARY will step down, but the SECONDARYs will not run for election as they believe the (former) PRIMARY will veto.

      Maybe, in the case that a node cannot see a candidate, they should not veto and instead vote when the actual election starts.

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          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-10364 Split Brain when the Primary loses the majority of the cluster, but the cluster can still see it.

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

          Improvement - An improvement or enhancement to an existing feature or task. DOCS-5700 Call res_init() after a failure of getaddrinfo()

          • Minor - P4 - Minor loss of function, or other problem where easy workaround is present.
          • Closed

            Activity

              People

              Assignee:
              milkie Eric Milkie
              Reporter:
              matt.dannenberg Matt Dannenberg
              Participants:
              Votes:
              8 Vote for this issue
              Watchers:
              18 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: