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Operators can still format clusters the same way as prior to this KIP. However, the --cluster-id flag now becomes optional. When When --cluster-id is specified, write meta.properties V2 with it. When --cluster-id is not specified, and the formatter's resolved MV supports ClusterIdRecord, write meta.properties V2 with an empty cluster.id. If the formatter's resolved MV does not support ClusterIdRecord, formatting will fail.
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