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Discussion thread: here

JIRA: here

Please keep the discussion on the mailing list rather than commenting on the wiki (wiki discussions get unwieldy fast).

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The controller will include the leader epoch of each partition when sending out an StopReplicaRequest. The broker will verify the epoch of each partitions and send an `FENCED_LEADER_EPOCH` error when the leader epoch received is older than the known one. When a topic is deleted, the leader epoch is not bumped. In this case, we will send a sentinel (-2) which overrides any existing epoch. Older version of the request will use a sentinel (-1) to indicate the the leader epoch is not present when the controller is still on the old version during the upgrade.

Starting from V3, only one StopReplica request will be sent by the controller, combining the partitions to be deleted and the partitions to stopped only.

Compatibility, Deprecation, and Migration Plan

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