第26章 Downgrading Streams for Apache Kafka

Procedure

1. Take note of any configuration changes made to the existing Cluster Operator resources (in the /install/cluster-operator directory). Any changes will be overwritten by the previous version of the Cluster Operator.
2. Revert your custom resources to reflect the supported configuration options available for the version of Streams for Apache Kafka you are downgrading to.

3. Update the Cluster Operator.

   1. Modify the installation files for the previous version according to the namespace the Cluster Operator is running in.

      On Linux, use:

      sed -i 's/namespace: .*/namespace: my-cluster-operator-namespace/' install/cluster-operator/*RoleBinding*.yaml

      On MacOS, use:

      sed -i '' 's/namespace: .*/namespace: my-cluster-operator-namespace/' install/cluster-operator/*RoleBinding*.yaml

   2. If you modified one or more environment variables in your existing Cluster Operator Deployment, edit the install/cluster-operator/060-Deployment-strimzi-cluster-operator.yaml file to use those environment variables.

4. When you have an updated configuration, deploy it along with the rest of the installation resources:

   oc replace -f install/cluster-operator

   Wait for the rolling updates to complete.

5. Get the image for the Kafka pod to ensure the downgrade was successful:

   oc get pod my-cluster-kafka-0 -o jsonpath='{.spec.containers[0].image}'

   The image tag shows the new Streams for Apache Kafka version followed by the Kafka version. For example, <strimzi_version>-kafka-<kafka_version>.

   You can also check the downgrade has completed successfully from the status of the Kafka resource.