Book Image

Learning YARN

By : Akhil Arora, Shrey Mehrotra, Shreyank Gupta
Book Image

Learning YARN

By: Akhil Arora, Shrey Mehrotra, Shreyank Gupta

Overview of this book

Today enterprises generate huge volumes of data. In order to provide effective services and to make smarter and more intelligent decisions from these huge volumes of data, enterprises use big-data analytics. In recent years, Hadoop has been used for massive data storage and efficient distributed processing of data. The Yet Another Resource Negotiator (YARN) framework solves the design problems related to resource management faced by the Hadoop 1.x framework by providing a more scalable, efficient, flexible, and highly available resource management framework for distributed data processing. This book starts with an overview of the YARN features and explains how YARN provides a business solution for growing big data needs. You will learn to provision and manage single, as well as multi-node, Hadoop-YARN clusters in the easiest way. You will walk through the YARN administration, life cycle management, application execution, REST APIs, schedulers, security framework and so on. You will gain insights about the YARN components and features such as ResourceManager, NodeManager, ApplicationMaster, Container, Timeline Server, High Availability, Resource Localisation and so on. The book explains Hadoop-YARN commands and the configurations of components and explores topics such as High Availability, Resource Localization and Log aggregation. You will then be ready to develop your own ApplicationMaster and execute it over a Hadoop-YARN cluster. Towards the end of the book, you will learn about the security architecture and integration of YARN with big data technologies like Spark and Storm. This book promises conceptual as well as practical knowledge of resource management using YARN.
Table of Contents (20 chapters)
Learning YARN
About the Authors
About the Reviewers

Using the Hadoop-YARN commands

YARN commands are invoked using the bin/yarn script in the Hadoop bundle. The basic syntax for the yarn command is:

yarn [--config confdir] COMMAND COMMAND_OPTIONS

Running the YARN script without any arguments, prints the description for all the commands. The config option is optional and its default value is $HADOOP_PREFIX/etc/hadoop.

YARN commands are classified as user and administration commands, as shown in the following figure:

The user commands

Hadoop-YARN clients execute the user commands. These clients connect to the YARN services using the configuration settings specified in the yarn-site.xml file. As specified in the previous chapter, the yarn-site.xml file and the other configuration files are all placed in the Hadoop configuration folder (/home/hduser/hadoop-2.5.1/etc/conf/). There are mainly six user commands in the Hadoop-YARN framework.


The jar command is used to run a jar file with the YARN code, that is, to submit a YARN application to the...