Book Image

Hadoop Beginner's Guide

Book Image

Hadoop Beginner's Guide

Overview of this book

Data is arriving faster than you can process it and the overall volumes keep growing at a rate that keeps you awake at night. Hadoop can help you tame the data beast. Effective use of Hadoop however requires a mixture of programming, design, and system administration skills."Hadoop Beginner's Guide" removes the mystery from Hadoop, presenting Hadoop and related technologies with a focus on building working systems and getting the job done, using cloud services to do so when it makes sense. From basic concepts and initial setup through developing applications and keeping the system running as the data grows, the book gives the understanding needed to effectively use Hadoop to solve real world problems.Starting with the basics of installing and configuring Hadoop, the book explains how to develop applications, maintain the system, and how to use additional products to integrate with other systems.While learning different ways to develop applications to run on Hadoop the book also covers tools such as Hive, Sqoop, and Flume that show how Hadoop can be integrated with relational databases and log collection.In addition to examples on Hadoop clusters on Ubuntu uses of cloud services such as Amazon, EC2 and Elastic MapReduce are covered.
Table of Contents (19 chapters)
Hadoop Beginner's Guide
Credits
About the Author
About the Reviewers
www.PacktPub.com
Preface
Index

Time for action – browsing default properties


Fortunately, the XML documents are not the only way of looking at the default values; there are also more readable HTML versions, which we'll now take a quick look at.

These files are not included in the Hadoop binary-only distribution; if you are using that, you can also find these files on the Hadoop website.

  1. Point your browser at the docs/core-default.html file within your Hadoop distribution directory and browse its contents. It should look like the next screenshot:

  2. Now, similarly, browse these other files:

    • Hadoop/docs/hdfs-default.html

    • Hadoop/docs/mapred-default.html

What just happened?

As you can see, each property has a name, default value, and a brief description. You will also see there are indeed a very large number of properties. Do not expect to understand all of these now, but do spend a little time browsing to get a flavor for the type of customization allowed by Hadoop.

Additional property elements

When we have previously set properties...