Shut down the current Kafka daemon, switch to the new version, and start the daemon:

su - kafka -c "/usr/hdp/current/kafka-broker/bin/kafka stop"
   hdp-select set kafka-broker 2.5.5.0-1100
   su - kafka -c "/usr/hdp/current/kafka-broker/bin/kafka start"

To verify that the Kafka daemon joined the cluster, create a topic and submit it to Kafka. Send a test message for that topic, and then validate that it was received by a consumer.

If the upgrade process fails, follow the steps in "Downgrading Kafka" to return to your previous version of Kafka.