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Kafka as a Messaging System
Kafka Cluster
Principles of distributed systems (multiple workers or nodes)
In Kafka, worker nodes are the Kafka brokers. Within a distributed system, there are different roles and responsibilities and there is a hierarchy that starts with a controller or supervisor. A controller is just a worker node like any other.
Once the controller is established and the workers are assigned and available, the cluster is distributed.
Reliable work distribution
Distributed consensus with Apache Zookeeper