Kafka Error FEATURE_UPDATE_FAILED
Error code 96 · Non-retriable Admin
Unable to update finalized features due to an unexpected server error.
Common Causes
- One or more brokers in the cluster are running a version that does not support the target feature level, blocking the finalization
- KRaft controller encountered an internal error while writing the feature update to the metadata log
- Cluster is in an inconsistent state (e.g., a broker is offline or not caught up) during the feature upgrade, causing the quorum to reject the write
Solutions
- Ensure all brokers are online and running the same Kafka version before attempting a feature upgrade — check with kafka-broker-api-versions.sh
- Check controller logs for the specific server error and resolve the underlying issue (disk full, network partition, quorum loss) before retrying
- Use kafka-features.sh describe to confirm current state and retry the upgrade only after all brokers have rejoined the cluster and caught up on metadata
Diagnostic Commands
# Check finalized feature versions in cluster
kafka-features.sh --bootstrap-server localhost:9092 describe
# Look for feature update events in logs
grep 'FEATURE_UPDATE_FAILED\|FeatureUpdateFailed\|finalize' /var/log/kafka/controller.log | tail -30Related APIs
This error can be returned by: UpdateFeatures
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