Book Image

Hadoop 2.x Administration Cookbook

By : Aman Singh
Book Image

Hadoop 2.x Administration Cookbook

By: Aman Singh

Overview of this book

Hadoop enables the distributed storage and processing of large datasets across clusters of computers. Learning how to administer Hadoop is crucial to exploit its unique features. With this book, you will be able to overcome common problems encountered in Hadoop administration. The book begins with laying the foundation by showing you the steps needed to set up a Hadoop cluster and its various nodes. You will get a better understanding of how to maintain Hadoop cluster, especially on the HDFS layer and using YARN and MapReduce. Further on, you will explore durability and high availability of a Hadoop cluster. You’ll get a better understanding of the schedulers in Hadoop and how to configure and use them for your tasks. You will also get hands-on experience with the backup and recovery options and the performance tuning aspects of Hadoop. Finally, you will get a better understanding of troubleshooting, diagnostics, and best practices in Hadoop administration. By the end of this book, you will have a proper understanding of working with Hadoop clusters and will also be able to secure, encrypt it, and configure auditing for your Hadoop clusters.
Table of Contents (20 chapters)
Hadoop 2.x Administration Cookbook
Credits
About the Author
About the Reviewers
www.PacktPub.com
Customer Feedback
Preface
Index

Nodes needed in the cluster


In this recipe, we will look at the number of nodes needed in the cluster based upon the storage requirements.

From the initial Disk space calculations recipe, we estimated that we need about 2 PB of storage for our cluster. In this recipe, we will estimate the number of nodes required for running a stable Hadoop cluster.

Getting ready

To step through the recipe, the user needs to have understood the Hadoop cluster daemons and their roles. It is recommended to have a cluster running with healthy HDFS and at least two Datanodes.

How to do it...

  1. Connect to the master1.cyrus.com master node in the cluster and switch to the user hadoop.

  2. Execute the command as shown here to see the Datanodes available and the disk space on each node:

    $ hdfs dfsadmin -report
  3. From the preceding command, we can tell the storage available per node, but we cannot tell the number of disks that make up that storage. Refer to the following screenshot for details:

  4. Login to a Datanode dn6.cyrus.com and...