HI, Malcolm, The configuration should be in *_coordinator_* topic. If your configuration of cleanup policy for this topic is compact only, you should not lose the configuration. If your configuration on this topic is a combination of compact + time retention (i.e. newer Kafka version on the broker side enabled this feature), you may lose your configuration.
-Yi On Wed, Sep 25, 2019 at 3:14 PM Malcolm McFarland <mmcfarl...@cavulus.com> wrote: > Hey folks, > > We implemented a custom grouper several months ago to do some basic > stats collection prior to startup. After our most recent restart, I > started seeing this error in our system: > > Grouper mismatch. Configured: > com.cavulus.grouper.OurSystemStreamPartitionGrouperFactory Actual: > org.apache.samza.container.grouper.stream.GroupByPartitionFactory > > Nothing has changed in either our Kafka cluster or our grouper code in > many months. In sleuthing out the cause, it occurred to me that > perhaps a data retention or cleanup policy was causing older messages > in the *_checkpoint_* or *_coordinator_* topics to be removed. > > I have two questions: > > 1) Where within these queues is the grouper configuration stored? > 2) Would a Kafka topic cleanup.policy of "compact" cause trouble here? > > Cheers, > Malcolm McFarland > Cavulus > > > This correspondence is from HealthPlanCRM, LLC, d/b/a Cavulus. Any > unauthorized or improper disclosure, copying, distribution, or use of > the contents of this message is prohibited. The information contained > in this message is intended only for the personal and confidential use > of the recipient(s) named above. If you have received this message in > error, please notify the sender immediately and delete the original > message. >