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  1. Core Server
  2. SERVER-27510

Compare only epochs instead of full chunk versions in CollectionMetadata::checkChunkIsValid()

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    • Type: Icon: Improvement Improvement
    • Resolution: Done
    • Priority: Icon: Major - P3 Major - P3
    • 3.4.2, 3.5.2
    • Affects Version/s: 3.4.1, 3.5.1
    • Component/s: Sharding
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    • Fully Compatible
    • v3.4
    • Sharding 2017-01-02
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      The check on the shard that the chunk's version sent by the config is the same as what the shard sees is a little counter productive: we bump the version of a random chunk on the donor with every migration, so a chunk that hasn't even moved away and back might get rejected for a moveChunk or splitChunk.

      Instead, we should just compare the chunk's epochs to protect against moving a chunk on a collection that was dropped and recreated.

            Assignee:
            esha.maharishi@mongodb.com Esha Maharishi (Inactive)
            Reporter:
            esha.maharishi@mongodb.com Esha Maharishi (Inactive)
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              Created:
              Updated:
              Resolved: