hadoop单机配置

配置环境变量(/etc/profile)

#set java environment

export JAVA_HOME=/usr/lib/java/jdk1.6.0_31

export JRE_HOME=/usr/lib/java/jdk1.6.0_31/jre

export HADOOP_HOME=/home/hadoop/hadoop

export CLASSPATH=$JAVA_HOME/lib:$JRE_HOME/lib:$CLASSPATH

export PATH=$PATH:$JAVA_HOME/bin:$JRE_HOME/bin:$HADOOP_HOME/bin

step 1. ssh的安装设置

由于Hadoop用ssh 通信，因此先进行免密码登录设定，

$apt-getinstallssh
$ssh-keygen-trsa-P''-f~/.ssh/id_rsa
$cat~/.ssh/id_rsa.pub>>~/.ssh/authorized_keys
$sshlocalhost
完成后请登入确认不用输入密码，（第一次登入需按enter键，第二次就可以直接登入到系统。
~$sshlocalhost
~$exit
~$sshlocalhost
~$exit

step 2. 安装java

由于 Sun Java Runtime 是执行 Hadoop 必备的工具，因此我们需要安装 JRE 或 JDK。这里我们直接安装 JDK，因为后面写程序仍旧需要用到 JDK 所提供的编译程序。目前 Ubuntu 9.04 提供的 JDK 套件最新版本为 Sun Java(TM) Development Kit (JDK) 6 ，套件名称为 sun-java6-jdk。并建议删除原本的 「 gcj 」 。
~$ sudo apt-get purge java-gcj-compat
~$ sudo apt-get install sun-java6-bin sun-java6-jdk sun-java6-jre

step 3. 下载安装Hadoop

•请至下载 Hadoop 0.20，并解开压缩文件到 /opt 路径。
•$ tar zxvf hadoop-0.20.0.tar.gz
•$ sudo mv hadoop-0.20.0 /opt/
•$ sudo chown -R hadoop:hadoop /opt/hadoop-0.20.0
•$ sudo ln -sf /opt/hadoop-0.20.0 /opt/hadoop

step 4. 设定 hadoop-env.sh

•进入 hadoop 目录，做进一步的设定。我们需要修改两个档案，第一个是 hadoop-env.sh，需要设定 JAVA_HOME, HADOOP_HOME, PATH 三个环境变量。
/opt$ cd hadoop/
/opt/hadoop$ cat >> conf/hadoop-env.sh << EOF
贴上以下信息
export JAVA_HOME=/usr/lib/jvm/java-6-sun
export HADOOP_HOME=/opt/hadoop
export PATH=$PATH:/opt/hadoop/bin
EOF

step 5. 设定 hadoop配置文件

•編輯 /opt/hadoop/conf/core-site.xml

<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://localhost:9000</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/tmp/hadoop/hadoop-${user.name}</value>
</property>
</configuration>
•編輯/opt/hadoop/conf/hdfs-site.xml
<configuration>
<property>
<name>dfs.replication</name>
<value>1</value>
</property>
</configuration>
•編輯/opt/hadoop/conf/mapred-site.xml
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>localhost:9001</value>
</property>
</configuration>

step 6. 格式化HDFS

•以上我们已经设定好 Hadoop 单机测试的环境，接着让我们来启动 Hadoop 相关服务，格式化 namenode， secondarynamenode, tasktracker
•$ cd /opt/hadoop
•$ source /opt/hadoop/conf/hadoop-env.sh
•$ hadoop namenode -format

执行画面如：
09/03/23 20:19:47 INFO dfs.NameNode: STARTUP_MSG:
/************************************************************
STARTUP_MSG: Starting NameNode
STARTUP_MSG: host = /localhost
STARTUP_MSG: args = [-format]
STARTUP_MSG: version = 0.20.3
STARTUP_MSG: build = https://svn.apache.org/repos/asf/hadoop/core/branches/branch-0.20 -r 736250; compiled by 'ndaley' on Thu Jan 22 23:12:08 UTC 2009
************************************************************/
09/03/23 20:19:47 INFO fs.FSNamesystem: fsOwner=hadooper,hadooper
09/03/23 20:19:47 INFO fs.FSNamesystem: supergroup=supergroup
09/03/23 20:19:47 INFO fs.FSNamesystem: isPermissionEnabled=true
09/03/23 20:19:47 INFO dfs.Storage: Image file of size 82 saved in 0 seconds.
09/03/23 20:19:47 INFO dfs.Storage: Storage directory /tmp/hadoop-hadooper/dfs/name has been successfully formatted.
09/03/23 20:19:47 INFO dfs.NameNode: SHUTDOWN_MSG:
/************************************************************
SHUTDOWN_MSG: Shutting down NameNode at /localhost
************************************************************/

step 7. 启动Hadoop

•接着用 start-all.sh 来启动所有服务，包含 namenode, datanode,
/opt/hadoop$ bin/start-all.sh
执行画面如：
starting namenode, logging to /opt/hadoop/logs/hadoop-hadooper-namenode-vPro.out
localhost: starting datanode, logging to /opt/hadoop/logs/hadoop-hadooper-datanode-vPro.out
localhost: starting secondarynamenode, logging to /opt/hadoop/logs/hadoop-hadooper-secondarynamenode-vPro.out
starting jobtracker, logging to /opt/hadoop/logs/hadoop-hadooper-jobtracker-vPro.out

step 8. 安装完毕测试

•启动之后，可以检查以下网址，来观看服务是否正常。Hadoop 管理接口 Hadoop Task Tracker 状态 Hadoop DFS 状态

•http://localhost:50030/ - Hadoop 管理接口

网址：http://jlins.iteye.com/blog/1070207