Hi, Hope you are safe and well!
Let me give a brief about my environment: OS: Ubuntu 18.04 Kafka Version: Confluent Kafka v5.5.1 ZooKeeper Version : 3.5.8 No.of Kafka Brokers: 3 No. of Zookeeper nodes: 3 I am working on a project where we are aiming to move out from our existing infrastructure lets call it A where Kafka and ZooKeeper clusters are hosted to a better infrastructure lets call it B but with no or minimal downtime. Once the cutover is done, we would like to terminate the old infrastructure A. I was able to use kafka-reassign-partitions.sh as per the steps mentioned in https://kafka.apache.org/documentation/#basic_ops_cluster_expansion to move the topics-partitions to the Kafka brokers I created in B. Please note that I have added 3 zookeeper nodes running in B into the zookeeper cluster in A and hence they were following the ZK leader in A. I was in the impression that since I had 6 nodes in the ZooKeeper ensemble, stopping the A side of ZooKeeper nodes would not cause an issue but I was wrong. As soon as I stopped the ZK process on the A nodes, B Zk nodes failed to accept any connections from Kafka and I assume it is because the leadership of ZK did not transfer to the ZK B nodes and failed the quorum resulting in this failure. I had to remove the version-2 folder inside the B Zk nodes and starting them 1 by 1 after removing the details of ZK A nodes from zookeeper.properties helped me to resolve the failure and run the cluster on infrastructure B. I know I failed miserably but this was a sandbox where I could afford the downtime but cannot in a production setup. I request your help and guidance to make it right. Please help! Thanks in advance. Regards,Rijo S Roy
