Release Notes - Kafka - Version 2.2.1

Below is a summary of the JIRA issues addressed in the 2.2.1 release of Kafka. For full documentation of the release, a guide to get started, and information about the project, see the Kafka project site.

Note about upgrades: Please carefully review the upgrade documentation for this release thoroughly before upgrading your cluster. The upgrade notes discuss any critical information about incompatibilities and breaking changes, performance changes, and any other changes that might impact your production deployment of Kafka.

The documentation for the most recent release can be found at https://kafka.apache.org/documentation.html.

Improvement

• [KAFKA-6789] - Add retry logic in AdminClient requests
• [KAFKA-8014] - Extend Connect integration tests to add and remove workers dynamically
• [KAFKA-8126] - Flaky Test org.apache.kafka.connect.runtime.WorkerTest.testAddRemoveTask
• [KAFKA-8348] - Document of kafkaStreams improvement

Bug

• [KAFKA-5141] - WorkerTest.testCleanupTasksOnStop transient failure due to NPE
• [KAFKA-7601] - Handle message format downgrades during upgrade of message format version
• [KAFKA-7633] - Kafka Connect requires permission to create internal topics even if they exist
• [KAFKA-7855] - Kafka Streams Maven Archetype quickstart fails to compile out of the box
• [KAFKA-7866] - Duplicate offsets after transaction index append failure
• [KAFKA-7895] - Ktable supress operator emitting more than one record for the same key per window
• [KAFKA-7939] - Flaky Test KafkaAdminClientTest#testCreateTopicsRetryBackoff
• [KAFKA-7946] - Flaky Test DeleteConsumerGroupsTest#testDeleteNonEmptyGroup
• [KAFKA-7974] - KafkaAdminClient loses worker thread/enters zombie state when initial DNS lookup fails
• [KAFKA-7976] - Flaky Test DynamicBrokerReconfigurationTest#testUncleanLeaderElectionEnable
• [KAFKA-7989] - Flaky Test RequestQuotaTest#testResponseThrottleTimeWhenBothFetchAndRequestQuotasViolated
• [KAFKA-8058] - ConnectRestExtensionContext does not return list of connectors from its ConnectClusterState
• [KAFKA-8062] - StateListener is not notified when StreamThread dies
• [KAFKA-8063] - Flaky Test WorkerTest#testConverterOverrides
• [KAFKA-8066] - ReplicaFetcherThread fails to startup because of failing to register the metric.
• [KAFKA-8091] - Flaky test DynamicBrokerReconfigurationTest#testAddRemoveSaslListener
• [KAFKA-8098] - Flaky Test AdminClientIntegrationTest#testConsumerGroups
• [KAFKA-8114] - Flaky Test DelegationTokenEndToEndAuthorizationTest#testNoGroupAcl
• [KAFKA-8121] - ZooKeeperClient session expiry thread may leave clients behind after close
• [KAFKA-8134] - ProducerConfig.LINGER_MS_CONFIG undocumented breaking change in kafka-clients 2.1
• [KAFKA-8142] - Kafka Streams fails with NPE if record contains null-value in header
• [KAFKA-8150] - Fix bugs in handling null arrays in generated RPC code
• [KAFKA-8157] - Missing "key.serializer" exception when setting "segment index bytes"
• [KAFKA-8190] - Keystore update without file change doesn't update SSLContext
• [KAFKA-8204] - Streams may flush state stores in the incorrect order
• [KAFKA-8227] - Missing Links in Duality of Streams and Tables section
• [KAFKA-8232] - Flaky test kafka.admin.TopicCommandWithAdminClientTest.testTopicDeletion
• [KAFKA-8240] - Source.equals() can fail with NPE
• [KAFKA-8241] - Dynamic update of keystore fails on listener without truststore
• [KAFKA-8248] - Producer may fail IllegalStateException
• [KAFKA-8254] - Suppress incorrectly passes a null topic to the serdes
• [KAFKA-8277] - Fix NPE in ConnectHeaders
• [KAFKA-8289] - KTable, Long> can't be suppressed
• [KAFKA-8298] - ConcurrentModificationException Possible when optimizing for repartition nodes
• [KAFKA-8304] - Connect susceptible to deadlock while registering REST extensions
• [KAFKA-8306] - Ensure consistency of checkpointed log start offset and current log end offset
• [KAFKA-8323] - Memory leak of BloomFilter Rocks object
• [KAFKA-8335] - Log cleaner skips Transactional mark and batch record, causing unlimited growth of __consumer_offsets
• [KAFKA-8352] - Connect System Tests are failing with 404

Test

• [KAFKA-8118] - Ensure that tests close ZooKeeper clients since they can impact subsequent tests