4. Getting started with External Apache ZooKeeper 3.4.6: Download & Installation

ZooKeeper is an open source Apache™ project which provides a centralized infrastructure and services that enable synchronization across a cluster. ZooKeeper maintains common objects needed in large cluster environments. Examples of these objects include configuration information, hierarchical naming space, and so on. Applications can leverage these services to coordinate distributed processing across large clusters.

Following services provided by Apache ZooKeeper makes it compatible with Apache Solr to provide benefits in the distributed computing environment.

• Naming service − Identifying the nodes in a cluster by name. It is similar to DNS, but for nodes.
• Configuration management − Latest and up-to-date configuration information of the system for a joining node.
• Cluster management − Joining / leaving of a node in a cluster and node status at real time.
• Leader election − Electing a node as leader for coordination purpose.
• Locking and synchronization service − Locking the data while modifying it. This mechanism helps you in automatic fail recovery while connecting other distributed applications like Apache HBase.
• Highly reliable data registry − Availability of data even when one or a few nodes are down.

This section covers the following topics,

• Downloading Zookeeper 3.4.6
• Installing Zookeeper 3.4.6

1. Downloading Zookeeper 3.4.6

We can download the current stable version of ZooKeeper from any of the www.apache.org. mirror website. http://ftp.jaist.ac.jp/pub/apache/zookeeper/

2. Installing Zookeeper 3.4.6

Once finished with downloading Zookeeper we can move on to the installation step.

Now, extract the downloaded ZooKeeper-3.4.6.tar.gz file on the system to start with ZooKeeper services.

Now, let’s move into the conf directory in the extracted Zookeeper folder.

Make a copy of the zoo_sample.cfg file present in the conf directory and rename it as zoo.cfg file.

Now, let’s make the required changes in the zoo.cfg file as required in the next section.