ZooKeeper can be relevant in the Databricks ecosystem in the following scenarios:

1. Kafka on Databricks: If you are running Apache Kafka on a Databricks cluster, ZooKeeper is typically used for cluster coordination, managing topics and partitions, and maintaining the overall state of the Kafka environment.
2. Other Distributed Systems: If you deploy other distributed systems on Databricks (e.g., Apache Hadoop, Apache HBase), they might rely on ZooKeeper for coordination and configuration management.

Key Points from Databricks Community:

• Kubernetes for High Availability (HA): Databricks primarily uses Kubernetes to ensure the high availability of its services rather than relying on ZooKeeper.
• Kafka 2.1 and ZooKeeper: Even in Kafka 2.1, ZooKeeper still significantly manages the Kafka cluster’s metadata and coordination.