Team, We are using kafka version 2.3.0 and we are facing issue with brokers replication <https://support.d2iq.com/s/feed/0D53Z00007KdrfHSAR> 1.Kafka has 6 brokers. 2.Mainly 7 topics exist in kafka cluster and each topic has 128 partitions. 3.Each partition has 3 in-sync-replicas and these are distributed among 6 kafka brokers. 4.All partitions has preferred leader and "Auto Leader Rebalance Enable" configuration enabled. Issue: We had a kafka broker-3 failure because of hardware issues and partitions having broker-3 as leader are disrupted. As per kafka official page, partitions should elect new leader once preferred leader fails.
[2020-06-01 14:02:25,029] ERROR [ReplicaManager broker=3] Error processing append operation on partition object-xxx-xxx-xx-na4-93 (kafka.server.ReplicaManager) org.apache.kafka.common.errors.NotEnoughReplicasException: Number of insync replicas for partition object-xxx-xxx-xx-na4-93 is [1], below required minimum [2] Above error message found in kafka logs, " object-xxx-xxx-xx-na4-93 " topic has 128 partition and 93rd partition has 3 replicas. It is distributed among (broker-3,broker-2,broker-4). Broker -3 is the preferred leader. When broker-3 failed, Leader position should move to any one of (broker-2,broker-4) but it didn't happened. As per error message, whenever leader is failing it is throwing error by stating only one insync replica available. Please help us in finding root cause for not selecting new leader. Thanks, Sudheer
