Book Image

HBase Administration Cookbook

By : Yifeng Jiang
Book Image

HBase Administration Cookbook

By: Yifeng Jiang

Overview of this book

As an Open Source distributed big data store, HBase scales to billions of rows, with millions of columns and sits on top of the clusters of commodity machines. If you are looking for a way to store and access a huge amount of data in real-time, then look no further than HBase.HBase Administration Cookbook provides practical examples and simple step-by-step instructions for you to administrate HBase with ease. The recipes cover a wide range of processes for managing a fully distributed, highly available HBase cluster on the cloud. Working with such a huge amount of data means that an organized and manageable process is key and this book will help you to achieve that.The recipes in this practical cookbook start from setting up a fully distributed HBase cluster and moving data into it. You will learn how to use all of the tools for day-to-day administration tasks as well as for efficiently managing and monitoring the cluster to achieve the best performance possible. Understanding the relationship between Hadoop and HBase will allow you to get the best out of HBase so the book will show you how to set up Hadoop clusters, configure Hadoop to cooperate with HBase, and tune its performance.
Table of Contents (16 chapters)
HBase Administration Cookbook
Credits
About the Author
Acknowledgement
About the Reviewers
www.PacktPub.com
Preface

Handling the "too many open files" error


In this recipe, we will describe how to troubleshoot the error shown in the following DataNode logs:

2012-02-18 17:43:18,009 ERROR org.apache.hadoop.hdfs.server.datanode.DataNode: DatanodeRegistration(10.166.111.191:50010, storageID=DS-2072496811-10.168.130.82-50010-1321345166369, infoPort=50075, ipcPort=50020):DataXceiver
java.io.FileNotFoundException: /usr/local/hadoop/var/dfs/data/current/subdir6/blk_-8839555124496884481 (Too many open files)
at java.io.RandomAccessFile.open(Native Method)
at java.io.RandomAccessFile.<init>(RandomAccessFile.java:216)
at org.apache.hadoop.hdfs.server.datanode.FSDataset.getBlockInputStream(FSDataset.java:1068)

Getting ready

To fix this issue, you will need root privileges on every node of the cluster. We assume you use the hadoop user to start your HDFS cluster.

How to do it...

To fix the "too many open files" error, execute the following steps on every node of the cluster:

  1. 1. Increase the open file number of...