Verify a Kafka's broker re-election when the current controller is isolated

Motivation

Testing your Zookeeper re-election process of a new controller broker helps to ensure high availability in your Kafka cluster. In addition, verify the behavior of your producers and consumers and verify what happens, e.g., to your message throughput while the re-election is happening or whether messages are lost.

Structure

We enforce the re-election of Kafka controller broker by blocking the network traffic to the current controller. By leveraging the 'check brokers'-step, we can validate that the new controller is elected and the old controller is detected as being down.