THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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Replica management
As the broker, configured with multiple log.dirs, catches up with metadata, and sees the partitions which it should be hosting, it will check the associated log directory UUID for each partition.
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For any new partitions, the active controller will use Uuid.ZERO as the initial value for log directory UUID for each replica. Each broker with multiple log.dirs hosting replicas then assigns a log directory UUID and communicates it back to the active controller using the new RPC AssignReplicasToDirs so that cluster metadata can be updated with the log directory assignment.
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