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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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    • Type: Icon: Bug Bug
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • None
    • Affects Version/s: 2.4.5
    • Component/s: Replication
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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.

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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.

      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.

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

              Created:
              Updated:
              Resolved: