Chapter 4. Developer Previews
Developer preview features included with AMQ Streams 2.6.
As a Kafka cluster administrator, you can toggle a subset of features on and off using feature gates in the Cluster Operator deployment configuration. The feature gates available as developer previews are at an alpha level of maturity and disabled by default.
Developer Preview features are not supported with Red Hat production service-level agreements (SLAs) and might not be functionally complete; therefore, Red Hat does not recommend implementing any Developer Preview features in production environments. This Developer Preview feature provides early access to upcoming product innovations, enabling you to test functionality and provide feedback during the development process. For more information about the support scope, see Developer Preview Support Scope.
4.1. UseKRaft feature gate Copy linkLink copied to clipboard!
Apache Kafka is in the process of phasing out the need for ZooKeeper. With the UseKRaft feature gate enabled, you can try deploying a Kafka cluster in KRaft (Kafka Raft metadata) mode without ZooKeeper.
This feature gate is experimental, intended only for development and testing, and must not be enabled for a production environment.
To use KRaft mode, you must also use KafkaNodePool resources to manage the configuration of groups of nodes. To enable the UseKRaft feature gate, specify +UseKRaft,+KafkaNodePools as values for the STRIMZI_FEATURE_GATES environment variable in the Cluster Operator configuration.
Enabling the UseKRaft feature gate
env:
- name: STRIMZI_FEATURE_GATES
value: +UseKRaft,+KafkaNodePools
env:
- name: STRIMZI_FEATURE_GATES
value: +UseKRaft,+KafkaNodePools
Currently, the KRaft mode in AMQ Streams has the following major limitations:
- Moving from Kafka clusters with ZooKeeper to KRaft clusters or the other way around is not supported.
- Controller-only nodes cannot undergo rolling updates or be updated individually.
- Upgrades and downgrades of Apache Kafka versions or the Strimzi operator are not supported. Users might need to delete the cluster, upgrade the operator and deploy a new Kafka cluster.
-
Only the Unidirectional Topic Operator is supported in KRaft mode. You can enable it using the
UnidirectionalTopicOperatorfeature gate. The Bidirectional Topic Operator is not supported and when theUnidirectionalTopicOperatorfeature gate is not enabled, thespec.entityOperator.topicOperatorproperty must be removed from theKafkacustom resource. -
JBOD storage is not supported. The
type: jbodstorage can be used, but the JBOD array can contain only one disk.