[KAFKA-10513] Newly added topic or partitions are not assigned to running consumer groups using static membership

• Type: Bug
• Status: Resolved
• Priority: Major
• Resolution: Won't Fix
• Affects Version/s: 2.6.0
• Component/s: consumer
• Assignee: Unassigned
• Reporter: Marlon Ou
• Created: 23/Sep/20 00:53
• Updated: 02/Oct/20 21:20
• Resolved: 02/Oct/20 21:20

Description

If consumers are polling messages from a certain topic with static membership and we add new partitions to this topic while the consumers are running, no partition reassignment is ever triggered (and hence messages published into the new partitions are never consumed). 

To reproduce, simply set group instance IDs on the consumers: 

props.setProperty("group.instance.id", instanceId);

And then while the static consumers are running, use Kafka's admin client to add more partitions to the topic:

adminClient.createPartitions(...)