How does Consumer Group and multiple topics assignment work

Ops
1

I understand that a consumer belonging to a single consumer group can consume messages from multiple topics.

While setting up ACL to multiple topics and a single consumer group, something like below will help me read from 2 topics while belonging to the same consumer group

ccloud kafka acl create --allow --service-account sa-55555 --operation READ --operation DESCRIBE --consumer-group java_example_group_1

ccloud kafka acl create --allow --service-account sa-55555 --operation READ --operation DESCRIBE --topic one
ccloud kafka acl create --allow --service-account sa-55555 --operation READ --operation DESCRIBE --topic two

Now if I want to remove access to one of the topics, but will modifying the ACL for the consumer group stop me from reading both the topics?

ccloud kafka acl delete --allow --service-account sa-55555 --operation READ --operation DESCRIBE --consumer-group java_example_group_1

ccloud kafka acl delete --allow --service-account sa-55555 --operation READ --operation DESCRIBE --topic one

I am confused as to how the behavior of consumer group works when it comes to deleting access to a single topic and not affecting the other topics it is associated with. Also what are the best practices around consumer group being assigned to multiple topics?

Any help is appreciated.

Thanks

2

I’m not sure why you want to remove the ACL for the consumer group? Consumer groups are a resource different from topics. The idea is to use one consumer group for each app, where when running multiple instances, it’s important that use the same consumer group. This way the different partitions to read from is shared accros instances, as are the committed offsets.