Confluent Platform 7.4 Release Notes

7.4 is a major release of Confluent Platform that provides you with Apache Kafka® 3.4, the latest stable version of Kafka.

The technical details of this release are summarized below.

For more information about the 7.4 release, check out the release blog.

Confluent Community / Kafka

  • In Confluent Platform 7.4, KRaft is now production ready for new clusters. KRaft is Kafka’s new metadata consensus protocol that is replacing ZooKeeper. For several years, the Kafka community has been developing a new way to run Kafka with self-managed metadata. This new mode, called KRaft mode, improves partition scalability and resiliency while simplifying deployments for Kafka. It also eliminates the need to run a ZooKeeper cluster alongside every Kafka cluster. For more information, see KRaft Overview.

  • There are some features that are currently supported in ZooKeeper mode that are not yet supported in KRaft mode in Confluent Platform 7.4:

    • Multi-region clusters
    • JBOD
    • Delegate Tokens
    • SCRAM
    • Quorum reconfiguration
    • RBAC in KRaft combined mode
    • TopicAclAuthorizer for Schema Registry

  • Combined mode, where a broker is also a controller, is not currently supported for production workloads. There are key security and feature gaps between combined mode and isolated mode in Confluent Platform.

  • Early Access for ZooKeeper to KRaft migrations for existing clusters is also available in Confluent Platform 7.4, with some exceptions:

    For more information about migrating from ZooKeeper to KRaft, see Migrate from ZooKeeper to KRaft (EA). For more information on current limitations of KRaft mode, see Limitations and known issues.

  • Confluent Platform 7.4 features Kafka 3.4. For a full list of the KIPs, features, and bug fixes, see the Apache Kafka release notes. For a summary of the improvements and changes in version 3.4, see Kafka 3.4 New Features and Updates on the Confluent blog, or the Kafka 3.4 release video that follows.

    • One of the highlights of Kafka 3.4 is the ability to migrate Kafka clusters from ZooKeeper to KRaft mode with no downtime. Migration is an early access feature, which is suitable for testing in non-production environments.

Cluster Management

Confluent for Kubernetes (formerly Confluent Operator)

New features:

  • CFK Blueprints are a new set of higher-level abstractions that enable teams to define a set of standardized ways (production, staging, develepment, QA, 0-RPO-availability, and more) that Confluent Platform must be deployed as, and then enables teams to stand up that Blueprint in any Kubernetes infrastructure.
  • Confluent Platform now supports KRaft-mode clusters for new deployments. CFK supports provisioning, managing and monitoring a KRaft mode cluster through a newly introduced KRaft controller custom resource.
  • Multi-Region Clusters (MRC) adds to the ability that CFK provides to Confluent Platform components to communicate with external access endpoints in a MRC deployment. This avoids the requirement in prior releases to change network settings to allow inter-Confluent Platform component communication via DNS resolution of internal endpoints. CFK has supported deploying and managing multi-region clusters since CFK 2.3.
  • CFK enables provisioning of separate certificates for internal communication between Confluent Platform components (except Connect and Kafka Rest Proxy), and external communications between clients and the Confluent Platform cluster.
  • CFK metrics available via Health+ to enable proactive support using product telemetry.
  • CFK allows for dynamic certificate loading for Kafka listeners. This enables you to update your Kafka broker certificates without requiring a Kafka cluster roll.

For the list of Confluent for Kubernetes release versions compatible with this release of Confluent Platform, see Kubernetes. See the Confluent for Kubernetes Release Notes for more details.

Ansible Playbooks for Confluent Platform

New features

  • Confluent Platform Ansible Playbooks for Confluent Platform tool for migrating to Ansible managed Confluent Platform environment called Confluent Platform-Ansible Playbooks for Confluent Platform Discovery.
  • Confluent Platform Ansible Playbooks for Confluent Platform playbook for KRaft based fresh Confluent Platform deployments.

Notable enhancements

  • Enhancement to use the Confluent Hub Client for installing local and remote Connect plugins.
  • Improved error handling for deploying connectors.
  • Support for custom Kerberos client configuration file and custom path.
  • Separate on-demand playbook for host validation.

For more information, see the Ansible Playbooks for Confluent Platform documentation.

ksqlDB

  • Added new built-in functions:
    • TRUNC - Truncates (rounds down to zero) the given value.
    • CORRELATION - Returns the Pearson correlation coefficient between the given columns.
  • New WITH parameter:
    • RETENTION_MS - Specifies the retention period in milliseconds for the underlying topic.

Schema Registry

  • Added support for Data Contracts in the form of Schema Metadata and Schema Rules.
    • Schema rules are only available with Confluent Enterprise.

How to download

Confluent Platform is available for download at https://www.confluent.io/download/. See the Install Confluent Platform On-Premises section for detailed information.

Important

The Confluent Platform package includes Confluent Server by default and requires a confluent.license key in your server.properties file. Starting with Confluent Platform 5.4.x, the Confluent Server broker checks for a license during start-up. You must supply a license string in each broker’s properties file using the confluent.license property as below:

confluent.license=LICENCE_STRING_HERE_NO_QUOTES

If you want to use the Kafka broker, download the confluent-community package. The Kafka broker is the default in all Debian or RHEL and CentOS packages.

For more information about migrating to Confluent Server, see Migrate Confluent Platform to Confluent Server.

To upgrade Confluent Platform to a newer version, check the Upgrade Confluent Platform documentation.

Supported versions and interoperability

Confluent Platform now supports RHEL 9. For the full list of supported versions and interoperability of Confluent Platform and its components, see Supported Versions and Interoperability for Confluent Platform.

Questions?

If you have questions regarding this release, feel free to reach out via the community mailing list or community Slack. Confluent customers are encouraged to contact our support directly.