58. What does Kafka need to operate?

Kafka cannot operate without ZooKeeper. Previously, ZooKeeper was used to manage cluster metadata, coordinate brokers, and control partition leaders. Although newer versions of Kafka (starting from 2.8) have introduced the ability to operate without ZooKeeper (KRaft mode), traditionally ZooKeeper is a required component.

Other options:

• Kafka can operate without broker replication, but fault tolerance is lost.
• Kafka can also operate without fine-tuned client configuration, but performance and reliability may suffer.
• The licensing agreement is not a technical requirement for Kafka to operate.

In summary, the correct answer is: Without ZooKeeper.