Hi , I wanted to understand the process for production upgrade of Kafka. As documented in the https://kafka.apache.org/documentation/#upgrade, it should be seamless.
I had a 3 node cluster(single topic, partitions=60, replication factor =2 )on which i was trying the same. As suggested, I first stopped first broker, did the property changes(inter.broker.protocol.version , log.message.format.version to 10.2.1) with 11 downloaded package and restarted it. It was rebuilding index and it took quite a bit of time. Thereafter, when I started another node with same steps, it failed. The partitions went offline. It seemed to me now the requirement for 2 Kafka10 nodes was not met, perhaps it wasnt able to recognize newly updated nodes. Regards, -Sameer.