Apache Zookeeper

Zookeeper is an open-source software tool used to coordinate distributed applications. It is used as a centralized service for maintaining configuration information, naming, providing distributed synchronization, and group services. Zookeeper provides a simple interface for applications to use, and its reliability and scalability make it a popular choice for many open-source applications. In this article, we will explore different open-source applications and how they utilize Zookeeper.

1. Apache Kafka: Apache Kafka is a distributed streaming platform that is widely used for building real-time data pipelines and streaming applications. Kafka uses Zookeeper to manage its cluster, track configuration changes, and keep track of Kafka topics, partitions, and consumers. Zookeeper ensures that Kafka's data is reliably stored and made available across the cluster.

Here is an example of how Kafka uses Zookeeper in its configuration file:

zookeeper.connect=localhost:2181

This line specifies the location of the Zookeeper service running on the local machine.

2. Apache HBase: Apache HBase is an open-source, distributed, column-oriented database designed to provide random, real-time access to big data. HBase uses Zookeeper for cluster coordination and to manage the assignment of regions to region servers. Zookeeper ensures that HBase's data is reliably stored and made available across the cluster.

Here is an example of how HBase uses Zookeeper in its configuration file:

hbase.zookeeper.quorum=localhost:2181

This line specifies the location of the Zookeeper service running on the local machine.

3. Apache Storm: Apache Storm is a distributed real-time computation system. Storm uses Zookeeper to manage its cluster and to coordinate the assignment of tasks to nodes in the cluster. Zookeeper ensures that Storm's data is reliably stored and made available across the cluster.

storm.zookeeper.servers:
   - "localhost"
storm.zookeeper.port: 2181