Apache Hadoop is a an open-source software framework written in Java for distributed storage and distributed process, it handles very large size of data sets by distributing it across computer clusters. Rather than rely on hardware to deliver high-availability, the library itself is designed to detect and handle failures at the application layer, so delivering a highly-available service on top of a cluster of computers, each of which may be prone to failures.
This article assumes you have at least basic knowledge of Linux, know how to use the shell, and most importantly, you host your site on your own VPS. The installation is quite simple and assumes you are running in the root account, if not you may need to add ‘sudo’ to the commands to get root privileges. We will show you through the step by step installation Apache Hadoop on an Ubuntu 16.04 Xenial Xerus server.
Install Apache Hadoop on Ubuntu 16.04 LTS
Step 1. First make sure that all your system packages are up-to-date by running these following apt-get commands in the terminal.
sudo apt-get update
sudo apt-get upgrade
Step 2. Installing Java (OpenJDK).
Since hadoop is based on java, make sure you have java jdk installed on the system. If you don’t have Java installed on your system, use following link to install it first.
Install Java JDK 8 on Ubuntu 16.04
[email protected] ~# java -version
java version "1.8.0_74"
Java(TM) SE Runtime Environment (build 1.8.0_74-b02)
Java HotSpot(TM) 64-Bit Server VM (build 25.74-b02, mixed mode)
Step 3. Installing Apache Hadoop.
To avoid security issues, we recommend to setup new Hadoop user group and user account to deal with all Hadoop related activities, following command:
sudo addgroup hadoopgroup
sudo adduser —ingroup hadoopgroup hadoopuser
After creating user, it also required to set up key based ssh to its own account. To do this use execute following commands:
su - hadoopuser
ssh-keygen -t rsa -P ""
cat /home/hadoopuser/.ssh/id_rsa.pub >> /home/hadoopuser/.ssh/authorized_keys
chmod 600 authorized_keys
ssh-copy-id -i ~/.ssh/id_rsa.pub slave-1
ssh slave-1
Download the latest stable version of Apache Hadoop, At the moment of writing this article it is version 2.8.1:
wget http://www-us.apache.org/dist/hadoop/common/hadoop-2.8.1/hadoop-2.8.1.tar.gz
tar xzf hadoop-2.8.1.tar.gz
mv hadoop-2.8.1 hadoop
Step 4. Configure Apache Hadoop.
Setup Hadoop environment variables. Edit ~/.bashrc file and append following values at end of file:
export HADOOP_HOME=/home/hadoop/hadoop
export HADOOP_INSTALL=$HADOOP_HOME
export HADOOP_MAPRED_HOME=$HADOOP_HOME
export HADOOP_COMMON_HOME=$HADOOP_HOME
export HADOOP_HDFS_HOME=$HADOOP_HOME
export YARN_HOME=$HADOOP_HOME
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_HOME/lib/native
export PATH=$PATH:$HADOOP_HOME/sbin:$HADOOP_HOME/bin
Apply environmental variables to current running session:
source ~/.bashrc
Now edit $HADOOP_HOME/etc/hadoop/hadoop-env.sh file and set JAVA_HOME environment variable:
export JAVA_HOME=/usr/jdk1.8.0_74/
Hadoop has many of configuration files, which need to configure as per requirements of your hadoop infrastructure. Lets start with the configuration with basic hadoop single node cluster setup:
cd $HADOOP_HOME/etc/hadoop
Edit core-site.xml:
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://localhost:9000</value>
</property>
</configuration>
Edit hdfs-site.xml:
<configuration>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.name.dir</name>
<value>file:///home/hadoop/hadoopdata/hdfs/namenode</value>
</property>
<property>
<name>dfs.data.dir</name>
<value>file:///home/hadoop/hadoopdata/hdfs/datanode</value>
</property>
</configuration>
Edit mapred-site.xml:
<configuration>
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>
</configuration>
Edit yarn-site.xml:
<configuration>
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
</configuration>
Now format namenode using following command, do not forget to check the storage directory:
hdfs namenode -format
Start all hadoop services use the following command:
cd $HADOOP_HOME/sbin/
start-dfs.sh
start-yarn.sh
You should observe the output to ascertain that it tries to start datanode on slave nodes one by one. To check if all services are started well use ‘jps‘ command:
jps
Step 5. Accessing Apache Hadoop.
Apache Hadoop will be available on HTTP port 8088 and port 50070 by default. Open your favorite browser and navigate to http://yourdomain.com:50070 or http://server-ip:50070. If you are using a firewall, please open port 8088 and 50070 to enable access to the control panel.
Congratulation’s! You have successfully installed Apache Hadoop. Thanks for using this tutorial for installing Apache Hadoop on Ubuntu 16.04 system. For additional help or useful information, we recommend you to check the official Apache Hadoop web site.
