Search icon CANCEL
Arrow left icon
Explore Products
Best Sellers
New Releases
Books
Videos
Audiobooks
Learning Hub
Conferences
Free Learning
Arrow right icon
Arrow up icon
GO TO TOP
Hadoop Real-World Solutions Cookbook- Second Edition

You're reading from   Hadoop Real-World Solutions Cookbook- Second Edition Over 90 hands-on recipes to help you learn and master the intricacies of Apache Hadoop 2.X, YARN, Hive, Pig, Oozie, Flume, Sqoop, Apache Spark, and Mahout

Arrow left icon
Product type Paperback
Published in Mar 2016
Publisher
ISBN-13 9781784395506
Length 290 pages
Edition 2nd Edition
Tools
Arrow right icon
Author (1):
Arrow left icon
Tanmay Deshpande Tanmay Deshpande
Author Profile Icon Tanmay Deshpande
Tanmay Deshpande
Arrow right icon
View More author details
Toc

Table of Contents (12) Chapters Close

Preface 1. Getting Started with Hadoop 2.X FREE CHAPTER 2. Exploring HDFS 3. Mastering Map Reduce Programs 4. Data Analysis Using Hive, Pig, and Hbase 5. Advanced Data Analysis Using Hive 6. Data Import/Export Using Sqoop and Flume 7. Automation of Hadoop Tasks Using Oozie 8. Machine Learning and Predictive Analytics Using Mahout and R 9. Integration with Apache Spark 10. Hadoop Use Cases Index

Setting the HDFS block size for all the files in a cluster


In this recipe, we are going to take a look at how to set a block size at the cluster level.

Getting ready

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

How to do it...

The HDFS block size is configurable for all files in the cluster or for a single file as well. To change the block size at the cluster level itself, we need to modify the hdfs-site.xml file.

By default, the HDFS block size is 128MB. In case we want to modify this, we need to update this property, as shown in the following code. This property changes the default block size to 64MB:

<property>
<name>dfs.block.size</name>
    <value>67108864</value>
    <description>HDFS Block size</description>
</property>

If you have a multi-node Hadoop cluster, you should update this file in the nodes, that is, NameNode and DataNode. Make sure you save these changes and restart the HDFS daemons:

/usr/local/hadoop...
lock icon The rest of the chapter is locked
Register for a free Packt account to unlock a world of extra content!
A free Packt account unlocks extra newsletters, articles, discounted offers, and much more. Start advancing your knowledge today.
Unlock this book and the full library FREE for 7 days
Get unlimited access to 7000+ expert-authored eBooks and videos courses covering every tech area you can think of
Renews at €18.99/month. Cancel anytime