Book Image

Hadoop Essentials

By : Shiva Achari
Book Image

Hadoop Essentials

By: Shiva Achari

Overview of this book

This book jumps into the world of Hadoop and its tools, to help you learn how to use them effectively to optimize and improve the way you handle Big Data. Starting with the fundamentals Hadoop YARN, MapReduce, HDFS, and other vital elements in the Hadoop ecosystem, you will soon learn many exciting topics such as MapReduce patterns, data management, and real-time data analysis using Hadoop. You will also explore a number of the leading data processing tools including Hive and Pig, and learn how to use Sqoop and Flume, two of the most powerful technologies used for data ingestion. With further guidance on data streaming and real-time analytics with Storm and Spark, Hadoop Essentials is a reliable and relevant resource for anyone who understands the difficulties - and opportunities - presented by Big Data today. With this guide, you'll develop your confidence with Hadoop, and be able to use the knowledge and skills you learn to successfully harness its unparalleled capabilities.
Table of Contents (15 chapters)
Hadoop Essentials
About the Author
About the Reviewers
Pillars of Hadoop – HDFS, MapReduce, and YARN


Hadoop is quite a fascinating and interesting project that has seen quite a lot of interest and contributions from the various organizations and institutions. Hadoop has come a long way, from being a batch processing system to a data lake and high-volume streaming analysis in low latency with the help of various Hadoop ecosystem components, specifically YARN. This progress has been substantial and has made Hadoop a powerful system, which can be designed as a storage, transformation, batch processing, analytics, or streaming and real-time processing system.

Hadoop project as a data lake can be divided in multiple phases such as data ingestion, data storage, data access, data processing, and data management. For each phase, we have different sub-projects that are tools, utilities, or frameworks to help and accelerate the process. The Hadoop ecosystem components are tested, configurable and proven and to build similar utility on our own it would take a huge amount of time and effort to achieve. The core of the Hadoop framework is complex for development and optimization. The smart way to speed up and ease the process is to utilize different Hadoop ecosystem components that are very useful, so that we can concentrate more on the application flow design and integration with other systems.

With the emergence of many useful sub-projects in Hadoop and other tools within the Hadoop ecosystem, the question that arises is which tool to use when and how effectively. This book is intended to complete the jigsaw puzzle of when and how to use the various ecosystem components, and to make you well aware of the Hadoop ecosystem utilities and the cases and scenarios where they should be used.

What this book covers

Chapter 1, Introduction to Big Data and Hadoop, covers an overview of big data and Hadoop, plus different use case patterns with advantages and features of Hadoop.

Chapter 2, Hadoop Ecosystem, explores the different phases or layers of Hadoop project development and some components that can be used in each layer.

Chapter 3, Pillars of Hadoop – HDFS, MapReduce, and YARN, is about the three key basic components of Hadoop, which are HDFS, MapReduce, and YARN.

Chapter 4, Data Access Components – Hive and Pig, covers the data access components Hive and Pig, which are abstract layers of the SQL-like and Pig Latin procedural languages, respectively, on top of the MapReduce framework.

Chapter 5, Storage Components – HBase, is about the NoSQL component database HBase in detail.

Chapter 6, Data Ingestion in Hadoop – Sqoop and Flume, covers the data ingestion library tools Sqoop and Flume.

Chapter 7, Streaming and Real-time Analysis – Storm and Spark, is about the streaming and real-time frameworks Storm and Spark built on top of YARN.

What you need for this book

A prerequisite for this book is good understanding of Java programming and basics of distributed computing will be very helpful and an interest to understand about Hadoop and its ecosystem components.


The code and syntax have been tested in Hadoop 2.4.1 and other compatible ecosystem component versions, but may vary in the newer version.

Who this book is for

If you are a system or application developer interested in learning how to solve practical problems using the Hadoop framework, then this book is ideal for you. This book is also meant for Hadoop professionals who want to find solutions to the different challenges they come across in their Hadoop projects. It assumes a familiarity with distributed storage and distributed applications.


In this book, you will find a number of text styles that distinguish between different kinds of information. Here are some examples of these styles and an explanation of their meaning.

Code words in text, database table names, folder names, filenames, file extensions, pathnames, dummy URLs, user input, and Twitter handles are shown as follows: "We can include other contexts through the use of the include directive."

A block of code is set as follows:

public static class MyPartitioner extends   org.apache.hadoop.mapreduce.Partitioner<Text,Text>

  public int getPartition(Text key, Text value, int numPartitions)
   int count =Integer.parseInt(line[1]);
    return 0;
    return 1;

And in Driver class

Any command-line input or output is written as follows:

hadoop fs -put /home/shiva/Samplefile.txt  /user/shiva/dir3/


Warnings or important notes appear in a box like this.


Tips and tricks appear like this.

Reader feedback

Feedback from our readers is always welcome. Let us know what you think about this book—what you liked or disliked. Reader feedback is important for us as it helps us develop titles that you will really get the most out of.

To send us general feedback, simply e-mail , and mention the book's title in the subject of your message.

If there is a topic that you have expertise in and you are interested in either writing or contributing to a book, see our author guide at

Customer support

Now that you are the proud owner of a Packt book, we have a number of things to help you to get the most from your purchase.

Downloading the example code

You can download the example code files from your account at for all the Packt Publishing books you have purchased. If you purchased this book elsewhere, you can visit and register to have the files e-mailed directly to you.


Although we have taken every care to ensure the accuracy of our content, mistakes do happen. If you find a mistake in one of our books—maybe a mistake in the text or the code—we would be grateful if you could report this to us. By doing so, you can save other readers from frustration and help us improve subsequent versions of this book. If you find any errata, please report them by visiting, selecting your book, clicking on the Errata Submission Form link, and entering the details of your errata. Once your errata are verified, your submission will be accepted and the errata will be uploaded to our website or added to any list of existing errata under the Errata section of that title.

To view the previously submitted errata, go to and enter the name of the book in the search field. The required information will appear under the Errata section.


Piracy of copyrighted material on the Internet is an ongoing problem across all media. At Packt, we take the protection of our copyright and licenses very seriously. If you come across any illegal copies of our works in any form on the Internet, please provide us with the location address or website name immediately so that we can pursue a remedy.

Please contact us at with a link to the suspected pirated material.

We appreciate your help in protecting our authors and our ability to bring you valuable content.


If you have a problem with any aspect of this book, you can contact us at , and we will do our best to address the problem.