今天决定重新搭建hadoop集群,如果是新手看这篇文章一定不要觉得很难,你只需要耐心和细心就ok了
准备工作
1.判断机器上是否有ssh服务,
[jinyang@OnlyKing Desktop]$ ssh -verison
OpenSSH_5.3p1, OpenSSL 1.0.0-fips 29 Mar 2010
Bad escape character 'rison'.
我的系统自带的,所以不用装了。
2.判断机器上是否有JDK
[jinyang@OnlyKing Desktop]$ java -version
java version "1.6.0_24"
OpenJDK Runtime Environment (IcedTea6 1.11.1) (rhel-1.45.1.11.1.el6-i386)
OpenJDK Server VM (build 20.0-b12, mixed mode)
[jinyang@OnlyKing Desktop]$ javac -version
javac 1.6.0_24
如果是系统自带的JDK,最好重装一下。http://blog.youkuaiyun.com/a15039096218/article/details/7378293
进入主题
1.下载和安装hadoop,我下载的是hadoop-0.20.2.tar.gz
解压文件:[root@OnlyKing Downloads]#tar-zxvfhadoop-0.20.2.tar.gz
移动文件:[root@OnlyKing Downloads]#mvhadoop-0.20.2/usr/local/
安装文件:[root@OnlyKing Downloads]#ln-shadoop-0.20.2hadoop
2.修改环境变量
[root@OnlyKing local]#vi/etc/profile
在文件的下面添加,不能直接在文件的上面添加
export HADOOP_HOME=/usr/local/hadoop
export PATH=$PATH:$HADOOP_HOME/bin
[root@OnlyKing local]#./etc/profile
[root@OnlyKing local]#vi/usr/local/hadoop/conf/hadoop.env.sh(配置JAVA_HOME)
[root@OnlyKing Desktop]# hadoop version
Hadoop 0.20.2
Subversion https://svn.apache.org/repos/asf/hadoop/common/branches/branch-0.20 -r 911707
Compiled by chrisdo on Fri Feb 19 08:07:34 UTC 2010
压轴大戏
1.NameNode配置
[hadoop@hadoop1 ~]# vi /etc/hosts
192.168.127.145 hadoop1
192.168.127.146 hadoop2
192.168.127.147 hadoop3
192.168.127.148 hadoop4
[root@OnlyKing conf]# vi core-site.xml
<configuration>
<property>
<name>fs.default.name</name>
<value>hdfs://hadoop1:9000</value>
</property>
</configuration>
[root@OnlyKing conf]# vi hdfs-site.xml
<configuration>
<property>
<name>dfs.replication</name>
<value>3</value>
</property>
<property>
<name>dfs.name.dir</name>
<value>/usr/local/hadoop/namenode/</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/usr/local/hadoop/tmp/</value>
</property>
</configuration>
[root@OnlyKing conf]# vi mapred-site.xml
<configuration>
<property>
<name>mapred.job.tracker</name>
<value>hadoop1:9001</value>
</property>
<property>
<name>mapred.tasktracker.map.tasks.maximum</name>
<value>4</value>
</property>
<property>
<name>mapred.tasktracker.reduce.tasks.maximum</name>
<value>4</value>
</property>
</configuration>
datanode配置 (只需修改hdfs-site.xml,mapred-site.xml和core-site.xml跟NameNode一样)
[hadoop@hadoop2 ~]$ vi hdfs-site.xml
<configuration>
<property>
<name>dfs.replication</name>
<value>3</value>
</property>
<property>
<name>dfs.data.dir</name>
<value>/home/hadoop/data</value>
</property>
<property>
<name>hadoop.tmp.dir</name>
<value>/usr/local/hadoop/tmp/</value>
</property>
<configuration>
[hadoop@hadoop1 conf]$ vi masters
hadoop1
[hadoop@hadoop1 conf]$ vi slaves
hadoop2
hadoop3
hadoop4
[hadoop@hadoop1 ~]$ start-all.sh
[hadoop@hadoop1 ~]$ stop-all.sh