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The leader will only accept requests signed with the most current key. This should not cause any major problems; if a follower attempts to make a request with an expired key (which should be quite rare and only occur if the request is made by a follower that is not fully caught up to the end of the config topic), the initial request will fail, but will be subsequently retried after a backoff period. This backoff period should leave sufficient room for the rebalance to completefollower to read the new session key from the config topic. If the first 240 requests fail with HTTP 403, it will be assumed that this is due to an out-of-date session key; a debug-level message about the subsequent retry will be logged in place of the current error-level log message of "Failed to reconfigure connector's tasks, retrying after backoff: " followed by a stack trace. Since the backoff period is 250 milliseconds, this should give at least one minute of leeway for an outdated key to be updated. If longer than that is required, the usual error-level log messages will begin to be generated by the worker.

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