Common Apache Kafka Exceptions and Their Causes

1、UnknownTopicOrPartitionException

org.apache.kafka.common.errors.UnknownTopicOrPartitionException:
This server does not host this topic-partition

Error: Partition data not found.

Analysis: Producer sent messages to a non‑existent topic; verify the topic exists or enable auto.create.topics.enable.

2、LEADER_NOT_AVAILABLE

WARN Error while fetching metadata with correlation id 0 : {test=LEADER_NOT_AVAILABLE} (org.apache.kafka.clients.NetworkClient

Error: Leader unavailable.

Analysis: Often occurs when the topic is being deleted or a leader election is in progress; use kafka-topics to check leader info and verify broker health, possibly restarting brokers.

3、NotLeaderForPartitionException

org.apache.kafka.common.errors.NotLeaderForPartitionException: This server is not the leader for that topic-partition

Error: Broker is no longer the leader for the partition.

Analysis: Happens during leader changes; investigate why the leader switched between brokers.

4、TimeoutException

org.apache.kafka.common.errors.TimeoutException: Expiring 5 record(s) for test-0: 30040 ms has passe

Error: Request timed out.

Analysis: Check where the timeout originates, verify network connectivity, and consider increasing request.timeout.ms.

5、RecordTooLargeException

WARN async.DefaultEventHandler: Produce request with correlation id 92548048 failed due to [TopicName,1]: org.apache.kafka.common.errors.RecordTooLargeException

Error: Message too large.

Analysis: Producer cannot handle the oversized message; increase request.timeout.ms or reduce batch.size.

6、Closing socket connection

Closing socket connection to/127,0,0,1.(kafka.network.Processor)

Error: Connection closed.

Analysis: Mismatch between producer and consumer client versions can cause repeated errors; ensure compatible versions.

7、ConcurrentModificationException

java.util.ConcurrentModificationException: KafkaConsumer is not safe for multi-threaded access

Error: Thread‑unsafe consumer usage.

Analysis: KafkaConsumer is not thread‑safe; avoid sharing a consumer across threads.

8、NetWorkException

[kafka-producer-network-thread | producer-1] o.apache.kafka.common.network.Selector : [Producer clientId=producer-1] Connection with / disconnected

Error: Network exception.

Analysis: Network connection interrupted; check broker network status.

9、ILLEGAL_GENERATION

ILLEGAL_GENERATION occurred while committing offsets for group

Error: Invalid generation.

Analysis: Consumer missed a rebalance because it spent too much time processing data; reduce max.poll.records, increase max.poll.interval.ms, or speed up processing.