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It is also possible for a write to ZK to fail. In this case,  we will want to stop making updates to the metadata log to avoid unbounded lag between KRaft and ZooKeeper. Since ZK brokers will be reading data like ACLs and dynamic configs from ZooKeeper, we should limit the amount of divergence between ZK and KRaft brokers by setting a bound on the amount of lag between KRaft and ZooKeeper.

Test Plan

Describe in few sentences how the KIP will be tested. We are mostly interested in system tests (since unit-tests are specific to implementation details). How will we know that the implementation works as expected? How will we know nothing broke?

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