can't listener some topics (there is three topic, but only find logs " partitions assigned:[ .....]" for two topics)

Question

I run a spring-boot application on linux server, it listened three topics, at first , it works well, but a few minutes, i found "(Re-)joining group ..." logs , and then only two topic has been listened, the other one can't listened , there is no error or warning logs can be found, i don't know how to resolve this problem, just have no idea what happend

at firs, i thought maybe my consumer config is not correct, i set max.poll.interval.ms:5000, max.poll.records:50.but it not works.

in my listener , i use this annotation to listened a topic

@KafkaListener(topics = "xxx")

i want this three topic all works, but now only two works

ps: at first , it all works ,just a few minutes later, after (Re-)joining group , one topic can't work well,and there is no error log or warning log

Answer 1

(Re-)joining group means that there is another consumer joining the same group and rebalance happened. Kafka tries to distribute partitions evenly between group members. That's might be the reason why you don't see the third topic to be polled by this your consumer. Just because it has gone to another one.

See more info about rebalance here: What does "Rebalancing" mean in Apache Kafka context?