Kafka consumer group in weird state

Question

My Kafka consumer group was running just fine. I stopped it and subscribed to additional topic. Since then sometimes it gives errror and doesn't consume messgaes:

Timeout during group to initialize

In kafka consumer group command output it shows negative lag then 0 lag even if no active streams.

Answer 1

Did you use any tool for inspecting Kafka? This one looks promising https://www.kafkatool.com/ and maybe gives you some information about the consumers.