Release Notes - Kafka - Version 2.6.2

Below is a summary of the JIRA issues addressed in the 2.6.2 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-8930] - MM2 documentation
• [KAFKA-12310] - Update zookeeper to 3.5.9
• [KAFKA-12400] - Upgrade jetty to fix CVE-2020-27223
• [KAFKA-12409] - Leaking gauge in ReplicaManager

Bug

• [KAFKA-10021] - When reading to the end of the config log, check if fetch.max.wait.ms is greater than worker.sync.timeout.ms
• [KAFKA-10340] - Source connectors should report error when trying to produce records to non-existent topics instead of hanging forever
• [KAFKA-10362] - When resuming Streams active task with EOS, the checkpoint file should be deleted
• [KAFKA-10413] - rebalancing leads to unevenly balanced connectors
• [KAFKA-10658] - ErrantRecordReporter.report always return completed future even though the record is not sent to DLQ topic yet
• [KAFKA-10678] - Re-deploying Streams app causes rebalance and task migration
• [KAFKA-10689] - Assignor can't determine number of partitions on FJK with upstream windowed repartition
• [KAFKA-10716] - Streams processId is unstable across restarts resulting in task mass migration
• [KAFKA-10763] - Task already exists error on same worker due to skip removal of tasks
• [KAFKA-10792] - Source tasks can block herder thread by hanging during stop
• [KAFKA-10793] - Race condition in FindCoordinatorFuture permanently severs connection to group coordinator
• [KAFKA-10798] - Failed authentication delay doesn't work with some SASL authentication failures
• [KAFKA-10895] - Basic auth extension's JAAS config can be corrupted by other plugins
• [KAFKA-12190] - Failure on Windows due to an UnsupportedOperationException when StateDirectory sets file permissions
• [KAFKA-12193] - Re-resolve IPs when a client is disconnected
• [KAFKA-12211] - NoSuchFileException will be thrown if hasPersistentStores is false when creating stateDir
• [KAFKA-12259] - Consolidated Status endpoint returns 500 when config provider can't find a config
• [KAFKA-12270] - Kafka Connect may fail a task when racing to create topic
• [KAFKA-12272] - Kafka Streams metric commit-latency-max and commit-latency-avg is always 0
• [KAFKA-12321] - the comparison function for uuid type should be 'equals' rather than '=='
• [KAFKA-12324] - Upgrade jetty to fix CVE-2020-27218
• [KAFKA-12326] - MM2 fails to start to due missing required configuration "bootstrap.servers"
• [KAFKA-12339] - Add retry to admin client's listOffsets
• [KAFKA-12340] - Recent change to use SharedTopicAdmin results in potential resource leak in deprecated backing store constructors
• [KAFKA-12343] - Recent change to use SharedTopicAdmin in KakfkaBasedLog fails with AK 0.10.x brokers
• [KAFKA-12389] - Upgrade of netty-codec due to CVE-2021-21290
• [KAFKA-12474] - Worker can die if unable to write new session key
• [KAFKA-12508] - Emit-on-change tables may lose updates on error or restart in at_least_once
• [KAFKA-12593] - Some Scala, Python, and Gradle files contain the wrong license header

Sub-task

• [KAFKA-10815] - EosTestDriver#verifyAllTransactionFinished should break loop if all partitions are verified
• [KAFKA-12624] - Fix LICENSE in 2.6