在Ubuntu上装Hadoop

在装Hadoop之前首先需要：

1.java1.6.x 最好是sun的，1.5.x也可以

2.ssh

安装ssh

 

$ sudo apt-get install ssh
$ sudo apt-get install rsync

 

 

下载Hadoop

从http://hadoop.apache.org/core/releases.html 下载最近发布的版本

 

最好为hadoop创建一个用户:

比如创建一个group为hadoop user为hadoop的用户以及组

 

$ sudo addgroup hadoop
$ sudo adduser --ingroup hadoop hadoop

 

解压下载的hadoop文件，放到/home/hadoop目录下 名字为hadoop 

配置JAVA_HOME:

 

gedit ~/hadoop/conf/hadoop-env.sh

 

将

 

 # The java implementation to use.  Required.
 # export JAVA_HOME=/usr/lib/j2sdk1.5-sun

 

 修改成java的安装目录：（我的是：/usr/lib/jvm/java-6-sun-1.6.0.15）

 

# The java implementation to use. Required.
export JAVA_HOME=/usr/lib/jvm/java-6-sun-1.6.0.15

 

 

现在可以使用单节点的方式运行：

 

$ cd hadoop
$ mkdir input
$ cp conf/*.xml input
$ bin/hadoop jar hadoop-*-examples.jar grep input output 'dfs[a-z.]+'
$ cat output/*

 

Pseudo-distributed方式跑:

 

配置ssh

 

$ su - hadoop
$ ssh-keygen -t rsa -P ""
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hadoop/.ssh/id_rsa):
Created directory '/home/hadoop/.ssh'.
Your identification has been saved in /home/hadoop/.ssh/id_rsa.
Your public key has been saved in /home/hadoop/.ssh/id_rsa.pub.
The key fingerprint is:
9d:47:ab:d7:22:54:f0:f9:b9:3b:64:93:12:75:81:27 hadoop@ubuntu

 

 让其不输入密码就能登录：

 

hadoop@ubuntu:~$ cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys

 

  使用：

 

$ ssh localhost

 

 看看是不是直接ok了。

 

 

hadoop配置文件：

conf/core-site.xml

 

<?xml version="1.0"?>
<?xml-stylesheet type="text/xsl" href="configuration.xsl"?>

<!-- Put site-specific property overrides in this file. -->

<configuration>
   <property>
	<name>hadoop.tmp.dir</name>
        <value>/home/hadoop/hadoop-datastore/hadoop-${user.name}</value>
   </property>
   <property>
	<name>fs.default.name</name>
	<value>hdfs://localhost:9000</value>
   </property>
</configuration>

 

 hadoop.tmp.dir配置为你想要的路径，${user.name}会自动扩展为运行hadoop的用户名

 

conf/hdfs-site.xml

 

<configuration>
  <property>
    <name>dfs.replication</name>
    <value>1</value>
  </property>
</configuration>

 

 dfs.replication为默认block复制数量

conf/mapred-site.xml

 

<configuration>
  <property>
    <name>mapred.job.tracker</name>
    <value>localhost:9001</value>
  </property>
</configuration>

 

 执行

 

格式化分布式文件系统：

 

$ bin/hadoop namenode -format

 

 启动hadoop：

 

$ bin/start-all.sh

 

 可以从

 

NameNode - http://localhost:50070/
JobTracker - http://localhost:50030/

 

 查看NameNode和JobTracker

 

运行例子：

 

 

$ bin/hadoop fs -put conf input

$ bin/hadoop jar hadoop-*-examples.jar grep input output 'dfs[a-z.]+'

 

look at the run result:

$ bin/hadoop fs -get output output
$ cat output/*

 

 

参考： 1、http://hadoop.apache.org/common/docs/current/quickstart.html
2、http://www.michael-noll.com/wiki/Running_Hadoop_On_Ubuntu_Linux_%28Single-Node_Cluster%29