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• A property named directory.id indicating the UUID for the log directory where the meta.properties file is located. The value is base64 encoded, like the cluster UUID.
• A property named directory.ids indicating the complete list of all UUIDs for each configured log directory. Values are base64 encoded and comma-separated. The order does not matter.

The meta.properties version field will be bumped from 1 to 2.

The UUIDs for each log directory are automatically generated by the tool if there isn't one assigned already in an existing meta.properties  file.

Having a persisted UUID at the root of each log directory allows the broker to identify the log directory regardless of the mount path.
Having a persisted list of all UUIDs for all configured log directories allows the broker to determine the UUIDs of unavailable (offline) log directories, as the meta.properties files for the offline log directories are likely to be unavailable.

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