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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.

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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.
    • Epic Link:

      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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              Assignee:
              milkie Eric Milkie
              Reporter:
              matt.dannenberg Matt Dannenberg
              Participants:
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              18 Start watching this issue

                Dates

                Created:
                Updated:
                Resolved: