Upgrade Confluent Platform¶

When you upgrade Confluent Platform from one version to another, we recommend that you perform the upgrade process separate from making other changes to your clusters, such as scaling up, changing configuration, or rotating credentials.

Note that there are certain configurations that cannot be updated on deployed clusters. See Upgrades and updates for this list.

Upgrade each Confluent Platform component as below:

In the component CR, update the component image.

CFK uses the following Confluent Platform component images:
- confluentinc/cp-server-connect
- confluentinc/cp-enterprise-control-center
- confluentinc/cp-server
- confluentinc/cp-ksqldb-server
- confluentinc/cp-enterprise-replicator
- confluentinc/cp-schema-registry
- confluentinc/cp-zookeeper
- confluentinc/cp-kafka-rest
The tag is the Confluent Platform release you want to upgrade to.
```
spec:
  image:
    application: <component image>:<tag>
```
For example, to upgrade Kafka to 7.3.5:
```
spec:
  image:
    application: confluentinc/cp-server:7.3.5
```
In the same component CR, update the CFK init container image. The image tag is the version of CFK, 2.5.5:
```
spec:
  image:
    init: confluentinc/confluent-init-container:2.5.5
```

When upgrading Kafka:

Set the following in the Kafka CR to match the currently installed version:

spec:
  configOverrides:
    server:
      - inter.broker.protocol.version=<current Kafka version>
      - log.message.format.version=<current Kafka version>

Upgrade Kafka:

kubectl apply -f <Kafka CR> --name <namespace>

After the Kafka brokers have been upgraded, update the properties in the Kafka CR:

spec:
  configOverrides:
    server:
      - inter.broker.protocol.version=3.3
      - log.message.format.version=3.3

Upgrade the component.

kubectl apply -f <component CR> --name <namespace>