Creating ZooKeeper and Kafka clusters
Most tutorials on running applications that can be distributed often only show how to run a single node and then you are left wondering how you would run this in production. In this section, you will build a three-node ZooKeeper and Kafka cluster. It will run on a single machine. However, I will split each instance into its own folder and each folder simulates a server. The only modification when running on different servers would be to change localhost to the server IP.
The next chapter will go into detail on the topic of Apache Kafka, but for now it is enough to understand that Kafka is a tool for building real-time data streams. Kafka was developed at LinkedIn and is now an Apache project. You can find Kafka on the web at http://kafka.apache.org. The website is shown in the following screenshot: