Colin Leroy created KAFKA-16296: ----------------------------------- Summary: Broker shrinks ISR when restarting Key: KAFKA-16296 URL: https://issues.apache.org/jira/browse/KAFKA-16296 Project: Kafka Issue Type: Bug Components: core Affects Versions: 3.6.1 Reporter: Colin Leroy
We have a rolling-restart problem we don't understand on a 3-node cluster. When stopping a broker, everything goes fine and the partitions are reassigned to the other brokers. When that broker restarts, it shrinks ISR because of "Out of sync replicas": {code:java} [2024-02-22 10:18:02,069] INFO [Partition OSS.PREPROD.Monitoring.Metric-5 broker=3] Shrinking ISR from 2,1,3 to 3. Leader: (highWatermark: 704389542, endOffset: 704395843). Out of sync replicas: (brokerId: 2, endOffset: -1, lastCaughtUpTimeMs: 1708593437335) (brokerId: 1, endOffset: -1, lastCaughtUpTimeMs: 1708593437335). (kafka.cluster.Partition) [2024-02-22 10:18:02,124] INFO [Partition OSS.PREPROD.Monitoring.Metric-5 broker=3] ISR updated to 3 (under-min-isr) and version updated to 1075 (kafka.cluster.Partition) {code} I do not understand why brokers 1 and 2 would be out of sync, it seems to me that given that brokers 1 and 2 were not restarted, they should be in sync. This, of course, causes problems as producers reconnect to broker 3 only to find the min ISR requirement is not fullfilled. Thanks in advance, Colin -- This message was sent by Atlassian Jira (v8.20.10#820010)