系统版本 : 64位CentOS6.6
hadoop版本： 1.2.1
jdk版本： jdk1.6.0_45
环境准备
1.主机分配
| 主机名 | ip |
| master | 1.0.0.0.10 |
| slave1 | 1.0.0.0.11 |
| slave2 | 1.0.0.0.12 |
| slave3 | 1.0.0.0.13 |
2.关闭防火墙和selinux（略）
3.配置dns（每一个节点都配置）
[root@master conf]# cat /etc/hosts 127.0.0.1 localhost localhost.localdomain localhost4 localhost4.localdomain4 ::1 localhost localhost.localdomain localhost6 localhost6.localdomain6 10.0.0.10 master 10.0.0.11 slave1 10.0.0.12 slave2 10.0.0.13 slave3
4.ssh免密登陆
生成公私钥，在 master 机器的虚拟机命令行下输入 ssh-keygen，一路回车，全部节点都执行
# cat ~/.ssh/id_rsa.pub >> ~/.ssh/authorized_keys
# scp .ssh/authorized_keys slave1:~/
# scp .ssh/authorized_keys slave2:~/
# scp .ssh/authorized_keys slave3:~/
然后将jdk和hadoop全部分发到各个slave节点
# cd /home/hadoop
# scp -r hadoop-1.2.1/ slave1:/home/hadoop/
# scp -r hadoop-1.2.1/ slave2:~/home/hadoop
# scp -r hadoop-1.2.1/ slave3:~/home/hadoop
# scp -r jdk1.6.0_45/ slave1:/home/hadoop/
# scp -r jdk1.6.0_45/ slave2:/home/hadoop/
# scp -r jdk1.6.0_45/ slave3:/home/hadoop/
由于实践部分主要以 Hadoop 1.0 环境为主，所以这主要介绍如何搭建 Hadoop 1.0 分布式环境。 整个分布式环境运行在带有 linux 操作系统的虚拟机上，至于虚拟机和 linux 系统的安 装这里暂不做过多介绍。
安装 Hadoop 分布式环境：
1) 安装jdk（所以节点）
# cd /home/hadoop 官网下载地址 版本为jdk1.6.0_45 # wget http://download.oracle.com/otn/java/jdk/6u45-b06/jdk-6u45-linux-x64.bin
# chmod +x jdk-6u45-linux-x64.bin
# ./jdk-6u45-linux-x64.bin
配置系统环境变量（方便使用jps命令查看java进程）
[root@master hadoop]# grep jdk ~/.bash_profile
PATH=$PATH:$HOME/bin:/home/hadoop/jdk1.6.0_45/bin/
2) 下载 Hadoop 安装包：（所有节点）
使用版本 hadoop-1.2.1
# useradd hadoop
# cd /home/hadoop
# rz 上传 hadoop-1.2.1.tar.gz 安装包
# tar xf hadoop-1.2.1.tar.gz
# 新增 tmp 目录
# mkdir /home/hadoop/hadoop-1.2.1/tmp
# cd conf
3) 配置 Hadoop：（所有节点）
[root@master conf]# pwd
/home/hadoop/hadoop-1.2.1/conf
[root@master conf]# cat masters
master
[root@master conf]# cat slaves
slave1
slave2
slave3
[root@master conf]# cat 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-1.2.1/tmp</value>
</property>
<property>
<name>fs.default.name</name>
<value>hdfs://10.0.0.10:9000</value>
</property>
</configuration>
[root@master conf]# cat mapred-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>mapred.job.tracker</name>
<value>http://10.0.0.10:9001</value>
</property>
</configuration>
[root@master conf]# cat hdfs-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>dfs.replication</name>
<value>3</value>
</property>
</configuration>
[root@master conf]# grep JAVA_HOME hadoop-env.sh #(注释掉原先默认的jdk路径换成自己的)
# The only required environment variable is JAVA_HOME. All others are
# set JAVA_HOME in this file, so that it is correctly defined on
# export JAVA_HOME=/usr/lib/j2sdk1.5-sun
export JAVA_HOME=/home/hadoop/jdk1.6.0_45/
4) hadoop的启动和停止
[root@master hadoop]# cd /home/hadoop/hadoop-1.2.1/bin/
#初始化hadoop文件系统
[root@master bin]# ./hadoop namenode -format
如果有error查看日志 百度百度，没什么问题的。
#开启脚本
[root@master bin]# ./start-all.sh
starting namenode, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-namenode-master.out
slave3: starting datanode, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-datanode-slave3.out
slave2: starting datanode, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-datanode-slave2.out
slave1: starting datanode, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-datanode-slave1.out
master: starting secondarynamenode, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-secondarynamenode-master.out
starting jobtracker, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-jobtracker-master.out
slave3: starting tasktracker, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-tasktracker-slave3.out
slave1: starting tasktracker, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-tasktracker-slave1.out
slave2: starting tasktracker, logging to /home/hadoop/hadoop-1.2.1/libexec/../logs/hadoop-root-tasktracker-slave2.out
#查看进程
主：
[root@master bin]# jps
4672 SecondaryNameNode
4495 NameNode
4861 Jps
4756 JobTracker
从：
[root@slave1 ~]# jps
3525 DataNode
3627 TaskTracker
3695 Jps
如果一切正常，应当有如上的一些进程存在。
#停止脚本
[root@master bin]# ./stop-all.sh
stopping jobtracker
slave3: stopping tasktracker
slave2: stopping tasktracker
slave1: stopping tasktracker
stopping namenode
slave3: stopping datanode
slave1: stopping datanode
slave2: stopping datanode
master: stopping secondarynamenode
5) 测试系统
#做个命令别名 [root@master bin]# grep hdfs /etc/bashrc alias hdfs='/home/hadoop/hadoop-1.2.1/bin/hadoop' #使用命令进行测试 [root@master bin]# hdfs fs -ls / Found 8 items drwxr-xr-x - root supergroup 0 2018-03-19 16:41 /dir drwxr-xr-x - root supergroup 0 2018-03-19 15:47 /home 有输出，就代表正常。