10.7. Enabling topic management for existing Kafka topics

Procedure

1. Create a KafkaTopic resource with a metadata.name that is the same as the Kafka topic.

   Or use spec.topicName if the name of the topic in Kafka would not be a legal OpenShift resource name.

   Example Kafka topic configuration

   apiVersion: kafka.strimzi.io/v1beta2
   kind: KafkaTopic
   metadata:
     name: my-topic-1
     labels:
       strimzi.io/cluster: my-cluster
   spec:
     partitions: 10
     replicas: 2

   In this example, the Kafka topic is named my-topic-1.

   The Topic Operator checks whether the topic is managed by another KafkaTopic resource. If it is, the older resource takes precedence and a resource conflict error is returned in the status of the new resource.

2. Apply the KafkaTopic resource:

   oc apply -f <topic_configuration_file>

3. Wait for the operator to update the topic in Kafka.

   The operator updates the Kafka topic with the spec of the KafkaTopic that has the same name.

4. Check the status of the KafkaTopic resource to make sure the request was successful:

   oc get kafkatopics my-topic-1 -o yaml

   Example topic with a Ready status

   apiVersion: kafka.strimzi.io/v1beta2
   kind: KafkaTopic
   metadata:
     generation: 1
     name: my-topic-1
     labels:
       strimzi.io/cluster: my-cluster
   spec:
     partitions: 10
     replicas: 2
   # ...
   status:
     observedGeneration: 1 

   1

   
     topicName: my-topic-1
     conditions:
     - type: Ready
       status: True
       lastTransitionTime: 20230301T103000Z

   1

   Successful reconciliation of the resource means the topic is now managed.

   The value of metadata.generation (the current version of the deployment) must match status.observedGeneration (the latest reconciliation of the resource).