Showing posts with label openssh-server. Show all posts
Showing posts with label openssh-server. Show all posts

Sunday, June 8, 2014

Initial study into apache hadoop single node cluster

If you have read big data article, you will definitely encountered the term, hadoop. Today, we are going to learn Apache Hadoop.

What is Apache Hadoop?

The Apache™ Hadoop® project develops open-source software for reliable, scalable, distributed computing.

The Apache Hadoop software library is a framework that allows for the distributed processing of large data sets across clusters of computers using simple programming models. It is designed to scale up from single servers to thousands of machines, each offering local computation and storage. 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.

There are links here and here further explain what is hadoop and its components.

I must admit to quickly setup and run single node cluster is difficult. Mainly because this is my first time learning hadoop and official documentation is not for the starter. So I google a few and got a few helpful links. The following setup is mainly for starter to get a feel on how it works. Sort of like hello world example of hadoop. As such goal is as simple as possible to get a feel of what it is.

Setup is a single node cluster, it work with current linux (debian) user environment and we can remove easily changes we've made after this tutorial. Note that example below is using my own username (jason), and it should work with your user ($HOME) environment too. User security is not a concern issue here as the objective is to learn the basic of hadoop here. A few system setup are needed and we start to prepare for the environment for hadoop.

Because this is a java library, a required JRE installed is needed. This article assume you have java installed and running. You can check it below. If you do not have java, google how to install JRE.
jason@localhost:~$ java -version
java version "1.7.0_55"
Java(TM) SE Runtime Environment (build 1.7.0_55-b13)
Java HotSpot(TM) 64-Bit Server VM (build 24.55-b03, mixed mode)

ssh daemon is required on your workstation. It is also recommend that openssh-client is installed as we will generate public and private key for automatic ssh login. Thus, apt-get install openssh-server openssh-client

Once both packages are installed, make sure sshd daemon is running and generate public and private key.
ssh-keygen -t rsa -P '' -f id_rsa_hadoop

with the above commands, we specified key type is rsa with empty passphrase so ssh will not prompt for passphrase and the key filename is id_rsa_hadoop. It's okay if you do not specify the key filename but because I have a few keys file, it is easy for me to identify and remove it later when this tutorial is done. The key should be available in your current user .ssh directory. To ensure ssh to localhost is automatic, echo your public key into authorized_keys file as a valid authorized key.
jason@localhost:~$ ls .ssh/
authorized_keys id_rsa id_rsa_hadoop id_rsa_hadoop.pub id_rsa.pub known_hosts

$ cat $HOME/.ssh/id_rsa_hadoop.pub >> $HOME/.ssh/authorized_keys

Right now if you ssh to localhost, you should logged without ssh asking for password in the terminal. That's it for the localhost setup. We will move on to the hadoop configuration.

Download a copy of hadoop. For this example, we are using hadoop version 2.4.0 . You can download it here. Then extract in the Desktop directory.
jason@localhost:~/Desktop$ tar -zxf hadoop-2.4.0.tar.gz
jason@localhost:~/Desktop$ cd hadoop-2.4.0
jason@localhost:~/Desktop/hadoop-2.4.0$ ls
bin etc include lib libexec LICENSE.txt logs NOTICE.txt README.txt sbin share

Then we will create directory for namenode and datanode.
jason@localhost:~/Desktop/hadoop-2.4.0$ pwd
/home/jason/Desktop/hadoop-2.4.0
jason@localhost:~/Desktop/hadoop-2.4.0$ mkdir -p hadoop_store/hdfs/namenode hadoop_store/hdfs/datanode

Then there are a few environment needed to be setup. Assuming you are using bash, enter the following into your .bashrc
#HADOOP VARIABLES START
export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_55
export HADOOP_INSTALL=/home/jason/Desktop/hadoop-2.4.0
export PATH=$PATH:$HADOOP_INSTALL/bin
export PATH=$PATH:$HADOOP_INSTALL/sbin
export HADOOP_MAPRED_HOME=$HADOOP_INSTALL
export HADOOP_COMMON_HOME=$HADOOP_INSTALL
export HADOOP_HDFS_HOME=$HADOOP_INSTALL
export YARN_HOME=$HADOOP_INSTALL
export HADOOP_COMMON_LIB_NATIVE_DIR=$HADOOP_INSTALL/lib/native
export HADOOP_OPTS="-Djava.library.path=$HADOOP_INSTALL/lib"
#HADOOP VARIABLES END

The only variable you need to take notice is JAVA_HOME and HADOOP_INSTALL. Once this is done, source immediately this file in your terminal as you will use the commands next.
jason@localhost:~/Desktop/hadoop-2.4.0$ source $HOME/.bashrc

We will now configured five xml properties files for hadoop, namely

  1. etc/hadoop/hadoop-env.sh

  2. etc/hadoop/core-site.xml

  3. etc/hadoop/hdfs-site.xml

  4. etc/hadoop/yarn-site.xml

  5. etc/hadoop/mapred-site.xml


It is assume you are still at current working directory such as below so you can easily edit the above files.
$ pwd
/home/jason/Desktop/hadoop-2.4.0

add the following content into etc/hadoop/hadoop-env.sh
export JAVA_HOME=/usr/lib/jvm/jdk1.7.0_55

add the following contents into etc/hadoop/core-site.xml
<property>
<name>fs.default.name</name>
<value>hdfs://localhost:9000</value>
</property>

add the following contents into etc/hadoop/hdfs-site.xml
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
<property>
<name>dfs.namenode.name.dir</name>
<value>file:/home/jason/Desktop/hadoop-2.4.0/hadoop_store/hdfs/namenode</value>
</property>
<property>
<name>dfs.datanode.data.dir</name>
<value>file:/home/jason/Desktop/hadoop-2.4.0/hadoop_store/hdfs/datanode</value>
</property>

add the following into etc/hadoop/yarn-site.xml
<property>
<name>yarn.nodemanager.aux-services</name>
<value>mapreduce_shuffle</value>
</property>
<property>
<name>yarn.nodemanager.aux-services.mapreduce.shuffle.class</name>
<value>org.apache.hadoop.mapred.ShuffleHandler</value>
</property>

for file etc/hadoop/mapred-site.xml, you can start by copy from etc/hadoop/mapred-site.xml.template
jason@localhost:~/Desktop/hadoop-2.4.0$ cp etc/hadoop/mapred-site.xml.template etc/hadoop/mapred-site.xml

then add the following into the file  etc/hadoop/mapred-site.xml
<property>
<name>mapreduce.framework.name</name>
<value>yarn</value>
</property>

Once it is done, that's it for the hadoop configuration and now run the command hdfs namenode -format . Below is the output in my terminal.
jason@localhost:~/Desktop/hadoop-2.4.0$ hdfs namenode -format
14/05/30 16:00:55 INFO namenode.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG: host = localhost/127.0.1.1
STARTUP_MSG: args = [-format]
STARTUP_MSG: version = 2.4.0
STARTUP_MSG: classpath = /home/jason/Desktop/hadoop-2.4.0/etc/hadoop:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/log4j-1.2.17.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/paranamer-2.3.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/avro-1.7.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jackson-xc-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jersey-core-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/protobuf-java-2.5.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jersey-server-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/hadoop-annotations-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jackson-mapper-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/httpcore-4.2.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jets3t-0.9.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jetty-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-beanutils-1.7.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/snappy-java-1.0.4.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jackson-jaxrs-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jasper-compiler-5.5.23.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/slf4j-api-1.7.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/asm-3.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-cli-1.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-beanutils-core-1.8.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/zookeeper-3.4.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/hadoop-auth-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jsr305-1.3.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-el-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-math3-3.1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jsp-api-2.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jaxb-api-2.2.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-lang-2.6.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jsch-0.1.42.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/mockito-all-1.8.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jaxb-impl-2.2.3-1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jettison-1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/servlet-api-2.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/activation-1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/xmlenc-0.52.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jetty-util-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/guava-11.0.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jasper-runtime-5.5.23.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-collections-3.2.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/slf4j-log4j12-1.7.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-codec-1.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/stax-api-1.0-2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-digester-1.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/xz-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-httpclient-3.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jackson-core-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-net-3.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/jersey-json-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/java-xmlbuilder-0.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/netty-3.6.2.Final.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-logging-1.1.3.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-io-2.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-compress-1.4.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/httpclient-4.2.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/junit-4.8.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/lib/commons-configuration-1.6.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/hadoop-common-2.4.0-tests.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/hadoop-nfs-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/common/hadoop-common-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/log4j-1.2.17.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jersey-core-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/protobuf-java-2.5.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jersey-server-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jackson-mapper-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jetty-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/asm-3.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-cli-1.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jsr305-1.3.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-el-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-daemon-1.0.13.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jsp-api-2.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-lang-2.6.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/servlet-api-2.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/xmlenc-0.52.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jetty-util-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/guava-11.0.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jasper-runtime-5.5.23.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-codec-1.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/jackson-core-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/netty-3.6.2.Final.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-logging-1.1.3.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/lib/commons-io-2.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/hadoop-hdfs-nfs-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/hadoop-hdfs-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/hdfs/hadoop-hdfs-2.4.0-tests.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/log4j-1.2.17.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jackson-xc-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jersey-core-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/protobuf-java-2.5.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jersey-server-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jersey-guice-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jackson-mapper-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jline-0.9.94.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jersey-client-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jetty-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jackson-jaxrs-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/asm-3.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-cli-1.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/zookeeper-3.4.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jsr305-1.3.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/guice-servlet-3.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jaxb-api-2.2.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-lang-2.6.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jaxb-impl-2.2.3-1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/aopalliance-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jettison-1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/servlet-api-2.5.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/activation-1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jetty-util-6.1.26.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/javax.inject-1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/guava-11.0.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-collections-3.2.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-codec-1.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/stax-api-1.0-2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/xz-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-httpclient-3.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jackson-core-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/guice-3.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/jersey-json-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/leveldbjni-all-1.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-logging-1.1.3.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-io-2.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/lib/commons-compress-1.4.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-applicationhistoryservice-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-tests-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-common-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-client-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-resourcemanager-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-common-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-applications-distributedshell-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-api-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-web-proxy-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-applications-unmanaged-am-launcher-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/yarn/hadoop-yarn-server-nodemanager-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/log4j-1.2.17.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/paranamer-2.3.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/avro-1.7.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/jersey-core-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/protobuf-java-2.5.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/jersey-server-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/hadoop-annotations-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/jersey-guice-1.9.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/jackson-mapper-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/snappy-java-1.0.4.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/asm-3.2.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/guice-servlet-3.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/aopalliance-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/junit-4.10.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/javax.inject-1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/xz-1.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/hamcrest-core-1.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/jackson-core-asl-1.8.8.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/guice-3.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/netty-3.6.2.Final.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/commons-io-2.4.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/lib/commons-compress-1.4.1.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-shuffle-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-common-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-app-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-hs-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-2.4.0-tests.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-hs-plugins-2.4.0.jar:/home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-core-2.4.0.jar:/contrib/capacity-scheduler/*.jar
STARTUP_MSG: build = http://svn.apache.org/repos/asf/hadoop/common -r 1583262; compiled by 'jenkins' on 2014-03-31T08:29Z
STARTUP_MSG: java = 1.7.0_55
************************************************************/
14/05/30 16:00:55 INFO namenode.NameNode: registered UNIX signal handlers for [TERM, HUP, INT]
14/05/30 16:00:55 INFO namenode.NameNode: createNameNode [-format]
14/05/30 16:00:57 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Formatting using clusterid: CID-a15244a5-fea6-42ad-ab38-92b9730521f5
14/05/30 16:00:58 INFO namenode.FSNamesystem: fsLock is fair:true
14/05/30 16:00:58 INFO namenode.HostFileManager: read includes:
HostSet(
)
14/05/30 16:00:58 INFO namenode.HostFileManager: read excludes:
HostSet(
)
14/05/30 16:00:58 INFO blockmanagement.DatanodeManager: dfs.block.invalidate.limit=1000
14/05/30 16:00:58 INFO blockmanagement.DatanodeManager: dfs.namenode.datanode.registration.ip-hostname-check=true
14/05/30 16:00:58 INFO util.GSet: Computing capacity for map BlocksMap
14/05/30 16:00:58 INFO util.GSet: VM type = 64-bit
14/05/30 16:00:58 INFO util.GSet: 2.0% max memory 889 MB = 17.8 MB
14/05/30 16:00:58 INFO util.GSet: capacity = 2^21 = 2097152 entries
14/05/30 16:00:58 INFO blockmanagement.BlockManager: dfs.block.access.token.enable=false
14/05/30 16:00:58 INFO blockmanagement.BlockManager: defaultReplication = 1
14/05/30 16:00:58 INFO blockmanagement.BlockManager: maxReplication = 512
14/05/30 16:00:58 INFO blockmanagement.BlockManager: minReplication = 1
14/05/30 16:00:58 INFO blockmanagement.BlockManager: maxReplicationStreams = 2
14/05/30 16:00:58 INFO blockmanagement.BlockManager: shouldCheckForEnoughRacks = false
14/05/30 16:00:58 INFO blockmanagement.BlockManager: replicationRecheckInterval = 3000
14/05/30 16:00:58 INFO blockmanagement.BlockManager: encryptDataTransfer = false
14/05/30 16:00:58 INFO blockmanagement.BlockManager: maxNumBlocksToLog = 1000
14/05/30 16:00:58 INFO namenode.FSNamesystem: fsOwner = jason (auth:SIMPLE)
14/05/30 16:00:58 INFO namenode.FSNamesystem: supergroup = supergroup
14/05/30 16:00:58 INFO namenode.FSNamesystem: isPermissionEnabled = true
14/05/30 16:00:58 INFO namenode.FSNamesystem: HA Enabled: false
14/05/30 16:00:58 INFO namenode.FSNamesystem: Append Enabled: true
14/05/30 16:00:59 INFO util.GSet: Computing capacity for map INodeMap
14/05/30 16:00:59 INFO util.GSet: VM type = 64-bit
14/05/30 16:00:59 INFO util.GSet: 1.0% max memory 889 MB = 8.9 MB
14/05/30 16:00:59 INFO util.GSet: capacity = 2^20 = 1048576 entries
14/05/30 16:00:59 INFO namenode.NameNode: Caching file names occuring more than 10 times
14/05/30 16:00:59 INFO util.GSet: Computing capacity for map cachedBlocks
14/05/30 16:00:59 INFO util.GSet: VM type = 64-bit
14/05/30 16:00:59 INFO util.GSet: 0.25% max memory 889 MB = 2.2 MB
14/05/30 16:00:59 INFO util.GSet: capacity = 2^18 = 262144 entries
14/05/30 16:00:59 INFO namenode.FSNamesystem: dfs.namenode.safemode.threshold-pct = 0.9990000128746033
14/05/30 16:00:59 INFO namenode.FSNamesystem: dfs.namenode.safemode.min.datanodes = 0
14/05/30 16:00:59 INFO namenode.FSNamesystem: dfs.namenode.safemode.extension = 30000
14/05/30 16:00:59 INFO namenode.FSNamesystem: Retry cache on namenode is enabled
14/05/30 16:00:59 INFO namenode.FSNamesystem: Retry cache will use 0.03 of total heap and retry cache entry expiry time is 600000 millis
14/05/30 16:00:59 INFO util.GSet: Computing capacity for map NameNodeRetryCache
14/05/30 16:00:59 INFO util.GSet: VM type = 64-bit
14/05/30 16:00:59 INFO util.GSet: 0.029999999329447746% max memory 889 MB = 273.1 KB
14/05/30 16:00:59 INFO util.GSet: capacity = 2^15 = 32768 entries
14/05/30 16:00:59 INFO namenode.AclConfigFlag: ACLs enabled? false
14/05/30 16:01:00 INFO namenode.FSImage: Allocated new BlockPoolId: BP-908722954-127.0.1.1-1401436859922
14/05/30 16:01:00 INFO common.Storage: Storage directory /home/jason/Desktop/hadoop-2.4.0/hadoop_store/hdfs/namenode has been successfully formatted.
14/05/30 16:01:01 INFO namenode.NNStorageRetentionManager: Going to retain 1 images with txid >= 0
14/05/30 16:01:01 INFO util.ExitUtil: Exiting with status 0
14/05/30 16:01:01 INFO namenode.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at localhost/127.0.1.1
************************************************************/

With this output, you should not see any error. Okay, all good and now, start the engine!
jason@localhost:~/Desktop/hadoop-2.4.0$ start-dfs.sh && start-yarn.sh
14/05/30 16:04:37 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Starting namenodes on [localhost]
localhost: starting namenode, logging to /home/jason/Desktop/hadoop-2.4.0/logs/hadoop-jason-namenode-localhost.out
localhost: starting datanode, logging to /home/jason/Desktop/hadoop-2.4.0/logs/hadoop-jason-datanode-localhost.out
Starting secondary namenodes [0.0.0.0]
0.0.0.0: starting secondarynamenode, logging to /home/jason/Desktop/hadoop-2.4.0/logs/hadoop-jason-secondarynamenode-localhost.out
14/05/30 16:05:09 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
starting yarn daemons
starting resourcemanager, logging to /home/jason/Desktop/hadoop-2.4.0/logs/yarn-jason-resourcemanager-localhost.out
localhost: starting nodemanager, logging to /home/jason/Desktop/hadoop-2.4.0/logs/yarn-jason-nodemanager-localhost.out
jason@localhost:~/Desktop/hadoop-2.4.0$

So you can check using jps if your hadoop is running. The expected hadoop processes are ResourceManager, SecondaryNameNode, NameNode, NodeManager and DataNode.
jason@localhost:~$ jps
22701 ResourceManager
22512 SecondaryNameNode
22210 NameNode
22800 NodeManager
6728 org.eclipse.equinox.launcher_1.3.0.v20120522-1813.jar
22840 Jps
22326 DataNode

You can access apache hadoop via the web interfaces:

Cluster status: http://localhost:8088
HDFS status: http://localhost:50070
Secondary NameNode status: http://localhost:50090

So that's looks good, everything is configured and now it is running fine. So we will continue by running a few examples.
jason@localhost:~/Desktop/hadoop-2.4.0$ hadoop jar /home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-2.4.0-tests.jar TestDFSIO -write -nrFiles 20 -fileSize 10
14/05/30 16:10:54 INFO fs.TestDFSIO: TestDFSIO.1.7
14/05/30 16:10:54 INFO fs.TestDFSIO: nrFiles = 20
14/05/30 16:10:54 INFO fs.TestDFSIO: nrBytes (MB) = 10.0
14/05/30 16:10:54 INFO fs.TestDFSIO: bufferSize = 1000000
14/05/30 16:10:54 INFO fs.TestDFSIO: baseDir = /benchmarks/TestDFSIO
14/05/30 16:10:55 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
14/05/30 16:10:57 INFO fs.TestDFSIO: creating control file: 10485760 bytes, 20 files
14/05/30 16:11:01 INFO fs.TestDFSIO: created control files for: 20 files
14/05/30 16:11:01 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
14/05/30 16:11:01 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
14/05/30 16:11:04 INFO mapred.FileInputFormat: Total input paths to process : 20
14/05/30 16:11:04 INFO mapreduce.JobSubmitter: number of splits:20
14/05/30 16:11:05 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1401437120030_0001
14/05/30 16:11:06 INFO impl.YarnClientImpl: Submitted application application_1401437120030_0001
14/05/30 16:11:06 INFO mapreduce.Job: The url to track the job: http://localhost:8088/proxy/application_1401437120030_0001/
14/05/30 16:11:06 INFO mapreduce.Job: Running job: job_1401437120030_0001
14/05/30 16:11:28 INFO mapreduce.Job: Job job_1401437120030_0001 running in uber mode : false
14/05/30 16:11:28 INFO mapreduce.Job: map 0% reduce 0%
14/05/30 16:12:30 INFO mapreduce.Job: map 7% reduce 0%
14/05/30 16:12:31 INFO mapreduce.Job: map 17% reduce 0%
14/05/30 16:12:34 INFO mapreduce.Job: map 23% reduce 0%
14/05/30 16:12:36 INFO mapreduce.Job: map 28% reduce 0%
14/05/30 16:12:37 INFO mapreduce.Job: map 30% reduce 0%
14/05/30 16:13:36 INFO mapreduce.Job: map 33% reduce 0%
14/05/30 16:13:39 INFO mapreduce.Job: map 40% reduce 0%
14/05/30 16:13:40 INFO mapreduce.Job: map 42% reduce 0%
14/05/30 16:13:42 INFO mapreduce.Job: map 52% reduce 0%
14/05/30 16:13:43 INFO mapreduce.Job: map 55% reduce 0%
14/05/30 16:13:44 INFO mapreduce.Job: map 58% reduce 0%
14/05/30 16:13:45 INFO mapreduce.Job: map 60% reduce 0%
14/05/30 16:14:47 INFO mapreduce.Job: map 67% reduce 2%
14/05/30 16:14:50 INFO mapreduce.Job: map 75% reduce 2%
14/05/30 16:14:51 INFO mapreduce.Job: map 78% reduce 22%
14/05/30 16:14:53 INFO mapreduce.Job: map 82% reduce 22%
14/05/30 16:14:54 INFO mapreduce.Job: map 85% reduce 22%
14/05/30 16:14:55 INFO mapreduce.Job: map 85% reduce 28%
14/05/30 16:15:37 INFO mapreduce.Job: map 88% reduce 28%
14/05/30 16:15:40 INFO mapreduce.Job: map 93% reduce 28%
14/05/30 16:15:42 INFO mapreduce.Job: map 95% reduce 32%
14/05/30 16:15:44 INFO mapreduce.Job: map 100% reduce 32%
14/05/30 16:15:45 INFO mapreduce.Job: map 100% reduce 67%
14/05/30 16:15:47 INFO mapreduce.Job: map 100% reduce 100%
14/05/30 16:15:49 INFO mapreduce.Job: Job job_1401437120030_0001 completed successfully
14/05/30 16:15:50 INFO mapreduce.Job: Counters: 50
File System Counters
FILE: Number of bytes read=1673
FILE: Number of bytes written=1965945
FILE: Number of read operations=0
FILE: Number of large read operations=0
FILE: Number of write operations=0
HDFS: Number of bytes read=4720
HDFS: Number of bytes written=209715278
HDFS: Number of read operations=83
HDFS: Number of large read operations=0
HDFS: Number of write operations=22
Job Counters
Killed map tasks=3
Launched map tasks=23
Launched reduce tasks=1
Data-local map tasks=23
Total time spent by all maps in occupied slots (ms)=1319128
Total time spent by all reduces in occupied slots (ms)=124593
Total time spent by all map tasks (ms)=1319128
Total time spent by all reduce tasks (ms)=124593
Total vcore-seconds taken by all map tasks=1319128
Total vcore-seconds taken by all reduce tasks=124593
Total megabyte-seconds taken by all map tasks=1350787072
Total megabyte-seconds taken by all reduce tasks=127583232
Map-Reduce Framework
Map input records=20
Map output records=100
Map output bytes=1467
Map output materialized bytes=1787
Input split bytes=2470
Combine input records=0
Combine output records=0
Reduce input groups=5
Reduce shuffle bytes=1787
Reduce input records=100
Reduce output records=5
Spilled Records=200
Shuffled Maps =20
Failed Shuffles=0
Merged Map outputs=20
GC time elapsed (ms)=14063
CPU time spent (ms)=127640
Physical memory (bytes) snapshot=5418561536
Virtual memory (bytes) snapshot=14516457472
Total committed heap usage (bytes)=4196401152
Shuffle Errors
BAD_ID=0
CONNECTION=0
IO_ERROR=0
WRONG_LENGTH=0
WRONG_MAP=0
WRONG_REDUCE=0
File Input Format Counters
Bytes Read=2250
File Output Format Counters
Bytes Written=78
14/05/30 16:15:50 INFO fs.TestDFSIO: ----- TestDFSIO ----- : write
14/05/30 16:15:50 INFO fs.TestDFSIO: Date & time: Fri May 30 16:15:50 MYT 2014
14/05/30 16:15:50 INFO fs.TestDFSIO: Number of files: 20
14/05/30 16:15:50 INFO fs.TestDFSIO: Total MBytes processed: 200.0
14/05/30 16:15:50 INFO fs.TestDFSIO: Throughput mb/sec: 1.6888468553671554
14/05/30 16:15:50 INFO fs.TestDFSIO: Average IO rate mb/sec: 1.840719223022461
14/05/30 16:15:50 INFO fs.TestDFSIO: IO rate std deviation: 0.7043729046488437
14/05/30 16:15:50 INFO fs.TestDFSIO: Test exec time sec: 289.58
14/05/30 16:15:50 INFO fs.TestDFSIO:

clean the project.
jason@localhost:~/Desktop/hadoop-2.4.0$ hadoop jar /home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-client-jobclient-2.4.0-tests.jar TestDFSIO -clean
14/05/30 16:20:03 INFO fs.TestDFSIO: TestDFSIO.1.7
14/05/30 16:20:03 INFO fs.TestDFSIO: nrFiles = 1
14/05/30 16:20:03 INFO fs.TestDFSIO: nrBytes (MB) = 1.0
14/05/30 16:20:03 INFO fs.TestDFSIO: bufferSize = 1000000
14/05/30 16:20:03 INFO fs.TestDFSIO: baseDir = /benchmarks/TestDFSIO
14/05/30 16:20:04 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
14/05/30 16:20:06 INFO fs.TestDFSIO: Cleaning up test files

another job example.
jason@localhost:~/Desktop/hadoop-2.4.0$ hadoop jar /home/jason/Desktop/hadoop-2.4.0/share/hadoop/mapreduce/hadoop-mapreduce-examples-2.4.0.jar pi 2 5
Number of Maps = 2
Samples per Map = 5
14/05/30 16:21:18 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Wrote input for Map #0
Wrote input for Map #1
Starting Job
14/05/30 16:21:23 INFO client.RMProxy: Connecting to ResourceManager at /0.0.0.0:8032
14/05/30 16:21:25 INFO input.FileInputFormat: Total input paths to process : 2
14/05/30 16:21:26 INFO mapreduce.JobSubmitter: number of splits:2
14/05/30 16:21:27 INFO mapreduce.JobSubmitter: Submitting tokens for job: job_1401437120030_0002
14/05/30 16:21:28 INFO impl.YarnClientImpl: Submitted application application_1401437120030_0002
14/05/30 16:21:28 INFO mapreduce.Job: The url to track the job: http://localhost:8088/proxy/application_1401437120030_0002/
14/05/30 16:21:28 INFO mapreduce.Job: Running job: job_1401437120030_0002
14/05/30 16:21:53 INFO mapreduce.Job: Job job_1401437120030_0002 running in uber mode : false
14/05/30 16:21:53 INFO mapreduce.Job: map 0% reduce 0%
14/05/30 16:22:18 INFO mapreduce.Job: map 100% reduce 0%
14/05/30 16:22:34 INFO mapreduce.Job: map 100% reduce 100%
14/05/30 16:22:35 INFO mapreduce.Job: Job job_1401437120030_0002 completed successfully
14/05/30 16:22:36 INFO mapreduce.Job: Counters: 49
File System Counters
FILE: Number of bytes read=50
FILE: Number of bytes written=280470
FILE: Number of read operations=0
FILE: Number of large read operations=0
FILE: Number of write operations=0
HDFS: Number of bytes read=530
HDFS: Number of bytes written=215
HDFS: Number of read operations=11
HDFS: Number of large read operations=0
HDFS: Number of write operations=3
Job Counters
Launched map tasks=2
Launched reduce tasks=1
Data-local map tasks=2
Total time spent by all maps in occupied slots (ms)=46538
Total time spent by all reduces in occupied slots (ms)=13821
Total time spent by all map tasks (ms)=46538
Total time spent by all reduce tasks (ms)=13821
Total vcore-seconds taken by all map tasks=46538
Total vcore-seconds taken by all reduce tasks=13821
Total megabyte-seconds taken by all map tasks=47654912
Total megabyte-seconds taken by all reduce tasks=14152704
Map-Reduce Framework
Map input records=2
Map output records=4
Map output bytes=36
Map output materialized bytes=56
Input split bytes=294
Combine input records=0
Combine output records=0
Reduce input groups=2
Reduce shuffle bytes=56
Reduce input records=4
Reduce output records=0
Spilled Records=8
Shuffled Maps =2
Failed Shuffles=0
Merged Map outputs=2
GC time elapsed (ms)=631
CPU time spent (ms)=7890
Physical memory (bytes) snapshot=623665152
Virtual memory (bytes) snapshot=2097958912
Total committed heap usage (bytes)=559939584
Shuffle Errors
BAD_ID=0
CONNECTION=0
IO_ERROR=0
WRONG_LENGTH=0
WRONG_MAP=0
WRONG_REDUCE=0
File Input Format Counters
Bytes Read=236
File Output Format Counters
Bytes Written=97
Job Finished in 73.196 seconds
Estimated value of Pi is 3.60000000000000000000

You can also create file and save on hadoop. You can read more at http://hadoop.apache.org/docs/r2.4.0/hadoop-project-dist/hadoop-common/FileSystemShell.html
jason@localhost:~$ hadoop fs -mkdir -p /user/hduser
14/05/30 16:27:31 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
jason@localhost:~$ hadoop fs -copyFromLocal dummy.txt dummy.txt
14/05/30 16:27:52 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
jason@localhost:~$ hadoop fs -ls
14/05/30 16:28:10 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Found 1 items
-rw-r--r-- 1 jason supergroup 13 2014-05-30 16:27 dummy.txt
jason@localhost:~$ hadoop fs -cat /user/hduser/dummy.txt
14/05/30 16:29:00 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
cat: `/user/hduser/dummy.txt': No such file or directory
jason@localhost:~$ hadoop fs -cat /user/jason/dummy.txt
14/05/30 16:29:11 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
hello world.
jason@localhost:~$ hadoop fs -ls /
14/05/30 16:29:24 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Found 3 items
drwxr-xr-x - jason supergroup 0 2014-05-30 16:20 /benchmarks
drwx------ - jason supergroup 0 2014-05-30 16:11 /tmp
drwxr-xr-x - jason supergroup 0 2014-05-30 16:27 /user
jason@localhost:~$ hadoop fs -rm dummy.txt
14/05/30 16:29:52 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
14/05/30 16:29:54 INFO fs.TrashPolicyDefault: Namenode trash configuration: Deletion interval = 0 minutes, Emptier interval = 0 minutes.
Deleted dummy.txt
jason@localhost:~$ hadoop fs -ls
14/05/30 16:30:03 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
jason@localhost:~$

Once you are done with hadoop cluster, you can shut it down using stop-dfs.sh && stop-yarn.sh
jason@localhost:~/Desktop/hadoop-2.4.0$ stop-dfs.sh && stop-yarn.sh
14/05/30 17:51:05 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
Stopping namenodes on [localhost]
localhost: stopping namenode
localhost: stopping datanode
Stopping secondary namenodes [0.0.0.0]
0.0.0.0: stopping secondarynamenode
14/05/30 17:51:25 WARN util.NativeCodeLoader: Unable to load native-hadoop library for your platform... using builtin-java classes where applicable
stopping yarn daemons
stopping resourcemanager
localhost: stopping nodemanager
no proxyserver to stop

You can remove/revert the changes you made for this tutorial.

/home/jason/Desktop/hadoop-2.4.0
/home/jason/.ssh/id_rsa_hadoop.pub
/home/jason/.ssh/id_rsa_hadoop
/home/jason/.ssh/authorized_keys
/home/jason/.bashrc

That's it for this lengthy article, hope you like it and if you learn something , remember to donate to us too!