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

An overview of web user interfaces

Similar to web interfaces available in the Hadoop 1.x version, the Hadoop 2.x version has web user interfaces for Hadoop services. Instead of the JobTracker service web UI, the web UI for ResourceManager is used to monitor applications and resources. A detailed explanation regarding the configurations related to the web UI's is given in the next chapter.

The following screenshot refers to the web-interface of Hadoop HDFS. Through the HDFS interface, you can:

  • Explore the HDFS metrics

  • View the list of DataNodes connected to the NameNode

  • Browse the file system, and so on

The following screenshot refers to the web-interface of YARN ResourceManager. It shows:

  • A summarized view of the cluster resource capabilities

  • A list of applications related to the cluster

  • A list of NodeManager nodes connected

  • The scheduler details, and so on

You can refer to the .pid files for the Hadoop daemons that are created in the /tmp folder of your node. These files contain the current process...