Re: [VOTE] 4.2.0 RC4

Hello,

Thanks Paolo for running Strimzi's tests!

As promised the system test results for RC4 can be found at
https://drive.google.com/drive/folders/1mFO6S1EvwMeTrM8w-ePTiRj6ko97Sv3A

The two consistently failing tests in my environment are:
*
'tests/kafkatest/tests/core/network_degrade_test.py::NetworkDegradeTest.test_rate@
{"task_name":"rate-1000-latency-50","device_name":"eth0","latency_ms":50,"rate_limit_kbit":1000000,"metadata_quorum":"COMBINED_KRAFT"}'
* tests/kafkatest/tests/tools/replica_verification_test.py::ReplicaVerificationToolTest.test_replica_lags@
{"metadata_quorum":"ISOLATED_KRAFT"}

Best,
Christo

On Wed, 11 Feb 2026 at 10:53, Paolo Patierno <paolo.patierno@gmail.com>
wrote:

> Hi,
> I downloaded the binaries and check the signature.
> I also ran all tests within the Strimzi project (Apache Kafka on
> Kubernetes) by using such binaries to build the container images.
> From regression to upgrade testing everything looks fine.
>
> +1 (non binding)
>
> Thanks,
> Paolo.
>
> On Tue, 10 Feb 2026 at 16:28, Christo Lolov <christololov@gmail.com>
> wrote:
>
> > Hello Kafka users, developers and client-developers,
> >
> > This is the RC4 candidate for release of Apache Kafka 4.2.0.
> >
> > This release has many exciting changes:
> > * Kafka Queues (Share Groups) is now production-ready with new
> > features like the RENEW acknowledgement type for extended processing
> > times, adaptive batching for coordinators, and comprehensive lag
> > metrics.
> > * Kafka Streams brings the server-side rebalance protocol to GA with a
> > limited feature set, adds dead letter queue support in exception
> > handlers, introduces anchored wall-clock punctuation for deterministic
> > scheduling, and gives users full control over whether to send a leave
> > group request on closing.
> > * This release also delivers significant improvements to consistency
> > and observability: CLI tools now feature standardized arguments like
> > --bootstrap-server across all tools, metric naming has been corrected
> > to follow the kafka.COMPONENT convention, and new idle ratio metrics
> > provide better visibility into controller and MetadataLoader
> > performance.
> > * Security is enhanced with a new allowlist connector client
> > configuration override policy, while thread-safety improvements to
> > RecordHeader eliminate concurrency risks.
> > * Additional highlights include external schema support in
> > JsonConverter for reduced message sizes, dynamic configuration for
> > remote log manager thread pools, and rack ID exposure in the Admin API
> > for consumer and share group members.
> >
> > Release notes for the 4.2.0 release:
> >
> https://dist.apache.org/repos/dist/dev/kafka/4.2.0-rc4/RELEASE_NOTES.html
> >
> > *** Please download, test and vote by Friday, February 13, 5pm UTC
> >
> > Kafka's KEYS file containing PGP keys we use to sign the release:
> > https://kafka.apache.org/KEYS
> >
> > * Release artifacts to be voted upon (source and binary):
> > https://dist.apache.org/repos/dist/dev/kafka/4.2.0-rc4/
> >
> > * Docker release artifacts to be voted upon:
> > apache/kafka:4.2.0-rc4
> > apache/kafka-native:4.2.0-rc4
> >
> > * Maven artifacts to be voted upon:
> > https://repository.apache.org/content/groups/staging/org/apache/kafka/
> >
> > * Javadoc:
> >
> https://dist.apache.org/repos/dist/dev/kafka/4.2.0-rc4/javadoc/index.html
> >
> > * Tag to be voted upon (off 4.2 branch) is the 4.2.0 tag:
> > https://github.com/apache/kafka/releases/tag/4.2.0-rc4
> >
> > * Documentation:
> > * Protocol:
> > https://github.com/apache/kafka-site/pull/785
> >
> > * Successful CI builds for the 4.2 branch:
> > Unit/integration tests:
> > https://github.com/apache/kafka/actions/runs/21860071096
> > System tests: I have started the tests in my environment and will share
> > test results in the next ~24 hours.
> >
> > * Successful Docker Image Github Actions Pipeline for 4.2 branch:
> > Docker Build Test Pipeline (JVM):
> > https://github.com/apache/kafka/actions/runs/21861574007
> > Docker Build Test Pipeline (Native):
> > https://github.com/apache/kafka/actions/runs/21861786570
> >
> > Thanks,
> > Christo
> >
>
>
> --
> Paolo Patierno
>
> *Senior Principal Software Engineer @ IBM**CNCF Ambassador*
>
> Twitter : @ppatierno <http://twitter.com/ppatierno>
> Linkedin : paolopatierno <http://it.linkedin.com/in/paolopatierno>
> GitHub : ppatierno <https://github.com/ppatierno>
>