Kafka Error INCONSISTENT_CLUSTER_ID
Error code 104 · Non-retriable Broker
The clusterId in the request does not match that found on the server.
Common Causes
- A broker's cluster ID stored in meta.properties does not match the cluster ID the KRaft controller presents — caused by copying data directories from another cluster
- Broker was re-provisioned or its data directory was replaced with data from a different Kafka cluster
- ZooKeeper-to-KRaft migration error where the cluster ID was regenerated but the broker's meta.properties was not updated
Solutions
- Check the cluster ID in /var/kafka/data/meta.properties on the broker versus the controller's cluster ID from kafka-metadata-quorum.sh describe --status; update or wipe the broker's data directory to match
- Wipe the broker's data directory and restart to trigger fresh registration with the correct cluster — do this only after confirming all replicas for its partitions exist on other brokers
- During ZK-to-KRaft migration, verify cluster IDs are consistent across all nodes before completing the migration
Diagnostic Commands
# Look for cluster ID errors in logs
cat /var/kafka/data/meta.properties | grep cluster.id
# Check KRaft metadata quorum status
kafka-metadata-quorum.sh --bootstrap-server localhost:9092 describe --status | head -5
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