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This checkpoint file is also created by the kafka-storage tool in the __cluster-metadata-0  directory. Now, it will also contain the data that used to be contained in the bootstrap.checkpoint file. It is important to note that the bootstrap records must be less than 8MB of total size if transactions are not supported, since that is the maximum batch size in bytes supported by KRaft.

RPC

ApiVersionsResponse

There are two fields in the ApiVersionsResponse that are used to describe the finalized feature version of the cluster. There is an existing issue where ApiVersionsResponse reports finalized feature versions even if the state of the cluster metadata partition is not known. Those two fields are documented as follow:

FinalizedFeaturesEpoch - The monotonically increasing epoch for the finalized features information. Valid values are >= 0. A value of -1 is special and represents unknown epoch.

FinalizedFeatures - List of cluster-wide finalized features. The information is valid only if FinalizedFeaturesEpoch >= 0.

The semantic of FinalizedFeatures will be changed slightly to not include any finalized feature version if the FinalizedFeaturesEpoch is -1.

Proposed Changes

Controller

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