10.4. Configuring Kafka topics

Procedure

1. Configure the KafkaTopic resource.

   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

   提示

   When modifying a topic, you can get the current version of the resource using oc get kafkatopic my-topic-1 -o yaml.

2. Create the KafkaTopic resource in OpenShift.

   oc apply -f <topic_config_file>

3. Wait for the ready status of the topic to change to True:

   oc get kafkatopics -o wide -w -n <namespace>

   Kafka topic status

   NAME         CLUSTER     PARTITIONS  REPLICATION FACTOR READY
   my-topic-1   my-cluster  10          3                  True
   my-topic-2   my-cluster  10          3
   my-topic-3   my-cluster  10          3                  True

   Topic creation is successful when the READY output shows True.

4. If the READY column stays blank, get more details on the status from the resource YAML or from the Topic Operator logs.

   Status messages provide details on the reason for the current status.

   oc get kafkatopics my-topic-2 -o yaml

   Details on a topic with a NotReady status

   # ...
   status:
     conditions:
     - lastTransitionTime: "2022-06-13T10:14:43.351550Z"
       message: Number of partitions cannot be decreased
       reason: PartitionDecreaseException
       status: "True"
       type: NotReady

   In this example, the reason the topic is not ready is because the original number of partitions was reduced in the KafkaTopic configuration. Kafka does not support this.

   After resetting the topic configuration, the status shows the topic is ready.

   oc get kafkatopics my-topic-2 -o wide -w -n <namespace>

   Status update of the topic

   NAME         CLUSTER     PARTITIONS  REPLICATION FACTOR READY
   my-topic-2   my-cluster  10          3                  True

   Fetching the details shows no messages

   oc get kafkatopics my-topic-2 -o yaml

   Details on a topic with a READY status

   # ...
   status:
     conditions:
     - lastTransitionTime: '2022-06-13T10:15:03.761084Z'
       status: 'True'
       type: Ready