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Yang commented on KAFKA-12890: ------------------------------ Hi [~dajac] I know this issue and PR have been closed for a while, just wonder if you have any broker-side log for this issue that you can share. Thanks! > Consumer group stuck in `CompletingRebalance` > --------------------------------------------- > > Key: KAFKA-12890 > URL: https://issues.apache.org/jira/browse/KAFKA-12890 > Project: Kafka > Issue Type: Bug > Affects Versions: 2.7.0, 2.6.1, 2.8.0, 2.7.1, 2.6.2 > Reporter: David Jacot > Assignee: David Jacot > Priority: Blocker > Fix For: 2.8.1, 3.0.0 > > > We have seen recently multiple consumer groups stuck in > `CompletingRebalance`. It appears that those group never receives the > assignment from the leader of the group and remains stuck in this state > forever. > When a group transitions to the `CompletingRebalance` state, the group > coordinator sets up `DelayedHeartbeat` for each member of the group. It does > so to ensure that the member sends a sync request within the session timeout. > If it does not, the group coordinator rebalances the group. Note that here, > `DelayedHeartbeat` is used here for this purpose. `DelayedHeartbeat` are also > completed when member heartbeats. > The issue is that https://github.com/apache/kafka/pull/8834 has changed the > heartbeat logic to allow members to heartbeat while the group is in the > `CompletingRebalance` state. This was not allowed before. Now, if a member > starts to heartbeat while the group is in the `CompletingRebalance`, the > heartbeat request will basically complete the pending `DelayedHeartbeat` that > was setup previously for catching not receiving the sync request. Therefore, > if the sync request never comes, the group coordinator does not notice > anymore. > We need to bring that behavior back somehow. -- This message was sent by Atlassian Jira (v8.20.10#820010)