[KAFKA-6421] consumer group can't show when use kafka-consumer-groups tool if the leader of __consumer_offsets partition for this group changed

• Type: Bug
• Status: Resolved
• Priority: Critical
• Resolution: Fixed
• Affects Version/s: 0.10.2.0, 0.11.0.1, 1.0.0
• Component/s: offset manager, tools
• Assignee: Vahid Hashemian
• Reporter: yuemeng
• Created: 04/Jan/18 03:48
• Updated: 24/Jan/18 04:24
• Resolved: 24/Jan/18 04:24

Description

follow steps will reproduce this problem:
1)there is a 3 brokers kafka cluster,use kafka-console-consumer.sh to consumer one topic and suppose group named "test-consumer-group",after a while, we stop consumer this topic.
2)suppose test-consumer-group will be write offset meta to partition 3 of __consumer_offsets,and the leader of partition 3 is broker 1.
3) and we scale the cluster to 5 nodes ,and reassign partititons,and leader of partition 3 is change to 0
4)then we use kafka-consumer-groups.sh --list can't show test-consumer-group,but the offset meta still in topic __consumer_offsets
and i found that:
protocolType will be change to empty for test-consumer-group after leader changed.
at last.

listAllGroupsFlattened.filter(_.protocolType == ConsumerProtocol.PROTOCOL_TYPE)

filter this test-consumer-group,so we can't use kafka-consumer-groups.sh to list it

Issue Links

• is part of: KAFKA-6287 Inconsistent protocol type for empty consumer groups