Hadoop Hangover: Launch a hadoop cluster CDH4 using Apache Whirr

Swathi VFebruary 13th, 2013Last Updated: March 4th, 2013

2 28 3 minutes read

This post is about how-to launch a CDH4 MRv1 or CDH4 Yarn cluster on EC2 instances. It’s said that you can launch a cluster with the help of Whirr and in a matter of 5 minutes! This is very true if and only if everything works out well!

Hopefully, this article helps you in that regard.

So, let’s row the boat…

Download the stable version of Apache Whirr ie. whirr-0.8.1.tar.gz from the following link whirr-0.8.1.tar.gz
Extract from the tarball and generate the key

$ tar -xzvf whirr-0.8.1.tar.gz
$ cd whirr-0.8.1

Generate the key

$ ssh-keygen -t rsa -P '' -f ~/.ssh/id_rsa_whirr
$ cd whirr-0.8.1

Make a properties file to launch the cluster with that configuration.

# Cluster name goes here
whirr.cluster-name=testcluster
 
# Change the number of machines in the cluster here
# Using 3 DN and TT and 1JT and NN# Ganglia is configured
whirr.instance-templates=1 hadoop-jobtracker+hadoop-namenode+ganglia-monitor+ganglia-metad,3 hadoop-datanode+hadoop-tasktracker+ganglia-monitor
 
# Install JAVA
whirr.java.install-function=install_openjdk
whirr.java.install-function=install_oab_java
 
## Install CDH4 MRV1
whirr.hadoop.install-function=install_cdh_hadoop
whirr.hadoop.configure-function=configure_cdh_hadoop
whirr.env.REPO=cdh4
 
# For EC2 set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables.
whirr.provider=aws-ec2
whirr.hardware-id=c1.xlarge
 
# Credentials should go here
whirr.identity=XXXXXXXXXXXXXXXXX
whirr.credential=XXXXXXXXXXXXXXXXXXXX
whirr.cluster-user=whirr
whirr.private-key-file=/home/ubuntu/.ssh/yourKey
whirr.public-key-file=/home/ubuntu/.ssh/yourKey.pub

Now let me tell you how to avoid getting headaches!

cluster name: Keep your cluster name simple. Avoid testCluster, testCluster1 etc. ie. No Caps, numerics..
Decide on the number of datanodes you want judiciously.
Your launch may not be successful, if java is not installed. Make sure the image has Java. However, this properties file takes care of that.
It will be good to go ahead with MRv1 for now and later switch to MRv2, when we get a production stable release.
This is the minimal set of configurations for launching a Hadoop cluster. But, you can do a lot performance tuning upon this.
I had launched this cluster from an ec2 instance, Initially i faced errors, regarding user. Setting the configuration below, solved the problem.

whirr.cluster-user=whirr

Set proper permissions for ~/.ssh and whirr-0.8.1 folder before launching.

Well, we are ready to launch the cluster. Name the properties file as ‘whirr_cdh.properties’.

$ cd whirr-0.8.1
$ bin/whirr launch-cluster --config whirr_cdh.properties

In the console you can see, links to Namenode and JobTracker Web UI. It also prints how to ssh to the instances in the end.

Now, you should be having the files generated. You will be able to see these files: instances, hadoop-proxy.sh and hadoop-site.xml
Starting the proxy

$ sh hadoop-proxy.sh

Open another terminal, and type
You should be able to access the HDFS.

$ export HADOOP_CONF_DIR=~/.whirr/testcluster/hadoop-site.xml
$ hadoop fs -ls /

You can alternatively download hadoop tarball and launch with

$ bin/hadoop --config ~/.whirr/testcluster fs -ls /

Okay! So I know that you will not be satisfied unless you a web UI

Now, Launch Firefox (3.0v+)
Download the FoxyProxy extension by clicking this link:https://addons.mozilla.org/en-US/firefox/addon/2464.
Steps to configure and access the UI
Select Tools > FoxyProxy > Options
Click the “Add New Proxy” button.
Select “Manual Proxy Configuration”
Enter “localhost” for the “Host or IP Address” field.
Enter “6666″ for the “Port” field.
Click on the “General” tab at the top of the dialog box.
Enter “EC2″ for the “Proxy Name” field.
Click on the “URL Patterns” tab at the top of the dialog box.
Click the “Add New Pattern” button.
Enter “EC2″ for the “Pattern Name” field.
Enter “*compute-1.amazonaws.com*, *.ec2.internal*, *.compute-1.internal*” for the “URL pattern” field (not case sensitive)
Select the “Whitelist” and “Wildcards” radio buttons.
Click the “OK” button to dismiss the new URL pattern dialog box.
Click the “OK” button to dismiss the new proxy dialog box.
Completely disable the Foxyproxy for now.
You should be able to see 2 proxy names after closing, default and EC2.
Click on “Use proxy EC2 for all URLs” from the pop-up menu of FoxyProxy
Copy the URL of JobTracker (can be seen while running proxy, ec2-***-**-***-**.********.amazonaws.com) and paste it in the browser.

So, we are good to go!

If you want to launch MRv2, use this.

## Cluster name goes here.
whirr.cluster-name=yarncluster
 
# Change the number of machines in the cluster here
whirr.instance-templates=1 hadoop-namenode+yarn-resourcemanager+mapreduce-historyserver,2 hadoop-datanode+yarn-nodemanager
 
# Install JAVA
whirr.java.install-function=install_openjdk
whirr.java.install-function=install_oab_java
 
## Install CDH4 Yarn
whirr.hadoop.install-function=install_cdh_hadoop
whirr.hadoop.configure-function=configure_cdh_hadoop
whirr.yarn.configure-function=configure_cdh_yarn
whirr.yarn.start-function=start_cdh_yarn
whirr.mr_jobhistory.start-function=start_cdh_mr_jobhistory
whirr.env.REPO=cdh4
whirr.env.MAPREDUCE_VERSION=2
 
# For EC2 set AWS_ACCESS_KEY_ID and AWS_SECRET_ACCESS_KEY environment variables.
whirr.provider=aws-ec2
whirr.hardware-id=c1.xlarge
 
# Credentials should go here
whirr.identity=XXXXXXXXXXXXXXXXX
whirr.credential=XXXXXXXXXXXXXXXXXXXXXXXXXXXXX
whirr.cluster-user=whirr
whirr.private-key-file=/home/ubuntu/.ssh/yourKey
whirr.public-key-file=/home/ubuntu/.ssh/yourKey.pub

and the same process!

Happy Learning!

Reference: Hadoop Hangover: Launch a hadoop cluster CDH4 using Apache Whirr from our JCG partner Swathi V at the * Techie(S)pArK * blog.