Book Image

Hadoop Real-World Solutions Cookbook - Second Edition

By : Tanmay Deshpande
Book Image

Hadoop Real-World Solutions Cookbook - Second Edition

By: Tanmay Deshpande

Overview of this book

Big data is the current requirement. Most organizations produce huge amount of data every day. With the arrival of Hadoop-like tools, it has become easier for everyone to solve big data problems with great efficiency and at minimal cost. Grasping Machine Learning techniques will help you greatly in building predictive models and using this data to make the right decisions for your organization. Hadoop Real World Solutions Cookbook gives readers insights into learning and mastering big data via recipes. The book not only clarifies most big data tools in the market but also provides best practices for using them. The book provides recipes that are based on the latest versions of Apache Hadoop 2.X, YARN, Hive, Pig, Sqoop, Flume, Apache Spark, Mahout and many more such ecosystem tools. This real-world-solution cookbook is packed with handy recipes you can apply to your own everyday issues. Each chapter provides in-depth recipes that can be referenced easily. This book provides detailed practices on the latest technologies such as YARN and Apache Spark. Readers will be able to consider themselves as big data experts on completion of this book. This guide is an invaluable tutorial if you are planning to implement a big data warehouse for your business.
Table of Contents (18 chapters)
Hadoop Real-World Solutions Cookbook Second Edition
Credits
About the Author
Acknowledgements
About the Reviewer
www.PacktPub.com
Preface
Index

Importing data from another Hadoop cluster


Sometimes, we may want to copy data from one HDFS to another either for development, testing, or production migration. In this recipe, we will learn how to copy data from one HDFS cluster to another.

Getting ready

To perform this recipe, you should already have a running Hadoop cluster.

How to do it...

Hadoop provides a utility called DistCp, which helps us copy data from one cluster to another. Using this utility is as simple as copying from one folder to another:

hadoop distcp hdfs://hadoopCluster1:9000/source hdfs://hadoopCluster2:9000/target

This would use a Map Reduce job to copy data from one cluster to another. You can also specify multiple source files to be copied to the target. There are a couple of other options that we can also use:

  • -update: When we use DistCp with the update option, it will copy only those files from the source that are not part of the target or differ from the target.

  • -overwrite: When we use DistCp with the overwrite option...