THIS IS A TEST INSTANCE. ALL YOUR CHANGES WILL BE LOST!!!!
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One important use for this file is the current directory structure does not allow us to reload the broker's view of topic ID on startup (perhaps after a failure). It is necessary to persist this file to disk so this information can be reloaded.
During LeaderAndIsrRequests, this file may be used to disambiguate topics safely and delete topics if necessary. More details on this process are explained in the LeaderAndIsrRequest v5 section.
It will be easy to update the file to include more fields in the future. This may assist with tooling purposes like mapping topic IDs to topic names.
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