Kafka Monthly Digest: September 2026

Releases

4.2.2

4.4.0

4.3.2

4.5.0

Kafka Improvement Proposals

• KIP-1373: Client Quota Utilization Metrics: Brokers expose several metrics to track quota usages by users. However these return the absolute usage values without the limits set by the cluster administrator. This KIP proposes adding new metrics exposing quota usage as percentages to help identify users near their limits and whether limits should be adjusted.
   

• KIP-1376: Support setting TLS named groups: The JVM uses TLS named groups to specify the key exchange algorithms it can use. Since Java 20, they can be set by application logic via the SSLParameters.setNamedGroups() API. This KIP proposes new configurations so users can configure named groups used by Kafka clients and servers. On supported JVMs, this enables using post-quantum cryptography (PQC) key exchange algorithms to prevent attacks like "Harvest now, decrypt later".
   

• KIP-1378: Allow Consumer Group Renaming in MirrorMaker 2 Checkpoint Connector: In MirrorMaker the replication policy allows renaming topics as they are mirrored to other clusters. Today when consumer groups are mirrored their names are kept as-is, and for that reason if a group already uses that name on the target cluster, MirrorMaker cannot automatically sync offsets (in that case it only emits checkpoints). This KIP proposes enabling replication policies to rename consumer groups like it's done for topic names.
   

Community Releases

• Debezium 3.7: Debezium is a Change Data Capture platform. This release includes major improvements to all of the existing connectors. It also introduces new connectors for TiDB, Milvus, and SQLite.
   

• kroxylicious 0.24.0: Kroxylicious is an open source pluggable framework for writing network proxies that understand the Apache Kafka protocol. This release adds SASL termination that enables the proxy to authenticate users. The project also decoupled its APIs from Apache Kafka classes, so plugin developers should now use classes under io.kroxylicious.kafka instead of org.apache.kafka. 

Blogs

• Why your Kafka topic ignores retention.ms (and how to fix it)
• Data liberation: Apache Kafka's native cluster mirroring
• Never lose quorum in Apache Kafka® - and what to do when you do
• Diskless Kafka: What Happens When Brokers Stop Owning the Data?