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  1. Kudu
  2. KUDU-2947

A replica with slow WAL may grant votes even if established leader is alive and well

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Details

    • Bug
    • Status: Resolved
    • Major
    • Resolution: Fixed
    • 0.5.0, 0.6.0, 0.7.0, 0.7.1, 0.8.0, 0.9.0, 0.9.1, 0.10.0, 1.0.0, 1.0.1, 1.1.0, 1.2.0, 1.3.0, 1.3.1, 1.4.0, 1.5.0, 1.6.0, 1.7.0, 1.8.0, 1.7.1, 1.9.0, 1.10.0
    • 1.11.0
    • consensus, master, tserver

    Description

      In some cases when WAL operations are slow, a follower replica may grant yes votes right after processing recent Raft transactions even if currently established leader replica is alive and well. Vote requests might come from so called disruptive replicas in the cluster. The disruptive replicas might ask for votes of higher Raft term than the current term with established and well being leader.

      In some cases that might lead to multiple successive election rounds even if there were no actual reason to re-elect leader replicas.

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        Issue Links

          is related to

          Sub-task - The sub-task of the issue KUDU-562 When a peer is partitioned, it should ask a majority if they still think the leader is alive

          • Major - Major loss of function.
          • Resolved
          relates to

          Improvement - An improvement or enhancement to an existing feature or task. KUDU-2452 Prevent follower from causing pre-elections when UpdateConsensus is slow

          • Major - Major loss of function.
          • Open

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              aserbin Alexey Serbin
              aserbin Alexey Serbin
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              Dates

                Created:
                Updated:
                Resolved: