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AlterIsrRequest => BrokerId BrokerEpoch [Topic [PartitionId LeaderAndIsr]]
  BrokerId => Int32
  BrokerEpoch => Int64
  Topic => String
  PartitionId => Int32
  LeaderAndIsr => Leader LeaderEpoch Isr CurrentZkVersion
    Leader => Int32
    LeaderEpoch => Int32
    Isr => [Int32]
    CurrentZkVersion => Int32

AlterIsrResponse => ErrorCode [Topic [PartitionId CurrentZkVersion ErrorCode]]
  ErrorCode => Int16
  Topic => String
  PartitionId => Int32
  CurrentZkVersion => Int32

Possible top-level errors:

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It can happen that a leader and ISR update fails after the AlterIsr was acknowledged. For example, if the controller fails before applying the changes, a new controller will be elected. It could also happen that there was already a pending change at the time the leader wanted to update ISR. In either case, the leader will receive a LeaderAndIsr update with the new version. The leader will check the status of current replicas at that time to see whether any additional changes are needed.Note that the controller returns the current zk version in the AlterIsr response. This is primarily intended for debugging purposes.

Compatibility, Deprecation, and Migration Plan

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