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If instead, a single entry is configured under log.dirs or log.dir, then the the controller will pre-select the directory for the replica, and the AssignReplicasToDirs RPC is only sent to correct assignments to UUID.LOST_DIR, as described above.
If the broker is configured with multiple log directories it remains FENCED until it can verify that all partitions are assigned to the correct log directories in the cluster metadata. This excludes the log directory that hosts the cluster metadata topic, if it is configured separately to a different path — using metadata.log.dir.
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