ZooKeeper 3.8.1

• Distributed coordination: ZooKeeper provides a way for distributed processes to coordinate with each other through a shared namespace.
• High availability: ZooKeeper is designed to be highly available even in the event of network partitions or other failures.
• Scalability: ZooKeeper is designed to scale to handle large numbers of clients and nodes in the cluster.
• Consistency: ZooKeeper provides a consistent view of the system state to all clients.
• Watch mechanism: ZooKeeper allows clients to watch for changes in the system state and receive notifications when changes occur.
• Simple API: ZooKeeper provides a simple API for developers to interact with the service.

• Configuration management: ZooKeeper is commonly used for managing configuration information in distributed systems. For example, it can be used to store the configuration information for a cluster of web servers.
• Synchronization: ZooKeeper can be used to synchronize access to shared resources in distributed systems. For example, it can be used to coordinate access to a shared database.

To use ZooKeeper, you would typically follow these steps:

1. Install and configure ZooKeeper on your servers.
2. Write your application code to interact with the ZooKeeper service using the provided API.
3. Start your application and connect to the ZooKeeper service.
4. Use the ZooKeeper API to read and write data to the service, and to set up watches for changes to the data.
5. Handle notifications and events from the ZooKeeper service in your application code

• ZooKeeper uses a replicated quorum-based protocol to achieve fault tolerance and consistency.
• ZooKeeper stores all data in memory for high performance, and uses disk for persistence.
• ZooKeeper provides both a Java client and a C client library for developers to interact with the service.
• ZooKeeper can be configured to use authentication and access control mechanisms to secure the data stored in the service.
• ZooKeeper provides support for multi-version concurrency control to ensure consistency in a distributed system.