Hi Alyssa, thanks for the feedback. On Mon, Sep 29, 2025 at 12:53 PM Alyssa Huang <[email protected]> wrote: > Along the lines of *chia_0*, what is the downgrade story for this change > (specifically downgrade after the provisioning is complete)?
I can make this explicit but none of the features in `kafka-storage format` are downgrade compatible. Once the storage tool formats a directory the same JAR must be used to start the JVMs. None of the records written to bootstrap.checkpoint or the zero checkpoint are guaranteed to be compatible with an older distribution. In other words the kafka-storage tool assumes that the JAR (distribution) used is the same JAR (distribution) that will be used to run the Kafka node (broker or controller). > It might be > worth mentioning in the compatibility section - it seems that users might > have to populate a bootstrap.checkpoint file that is consistent with > whatever was already written to the zero checkpoint if they do not want to > reformat? Once a directory has been formatted, it cannot be reformatted. If the user passes --ignore-formatted, the log directory is skipped. If the user doesn't pass --ignore-formatted, the format command will fail. Thanks, -- -José
