// This module is included in the following assemblies:
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// assembly-upgrading-kafka-versions.adoc

[id='con-kafka-upgrades-using-cluster-operator-{context}']
= Kafka upgrades using the Cluster Operator

How the Cluster Operator will perform an upgrade depends on the differences between:

* The interbroker protocol version of the two Kafka versions
* The log message format version of the two Kafka versions
* The version of Zookeeper used by the two Kafka versions

When each of these versions is the same, as is typically the case for a patch level upgrade (for example 2.0.0 to 2.0.1), then the Cluster Operator can perform the upgrade using a single rolling update of the Kafka brokers. 
When one or more of these versions differ, the Cluster Operator will require two or three rolling updates of the Kafka brokers to perform the upgrade.

