1.关闭防火墙和selinux
service iptables stop #关闭
service iptables status ?#查看状态
cd /etc/sysconfig/selinux修改为disable
2.设置为静态的IP
3.IP和主机名要一致
hostname查看主机名
cd /etc/hosts ??
vim hosts修改ip地址后的主机名，与hostname一致
修改/etc/sysconfig/network中HOSTNAME的值为hostname的值
/etc/rc.d/init.d/network?restart 重启
来源：http://blog.csdn.net/shirdrn/article/details/6562292
4.java环境变量配置
cd /opt/software/hadoop
?cd hadoop-1.2.1
cd conf
vim??hadoop-env.sh
设置文件中的JAVA_HOME，并将#去掉
5.输入命令
[root@localhost root]# ssh-keygen -t rsa
之后一直点回车
[root@localhost root]# cd .ssh
[root@localhost .ssh]# ls
id_rsa ?id_rsa.pub
[root@localhost .ssh]# ll
total 8
-rw------- ? ?1 root ? ? root ? ? ? ? ?887 Jun 20 03:48 id_rsa
-rw-r--r-- ? ?1 root ? ? root ? ? ? ? ?219 Jun 20 03:48 id_rsa.pub
[root@localhost .ssh]# cp ~/.ssh/id_rsa.pub ~/.ssh/authorized_keys
[root@localhost .ssh]# ll
[root@localhost .ssh]# ssh localhost
The authenticity of host 'localhost (192.168.235.10)' can't be established.
RSA key fingerprint is 05:36:83:f3:3c:d7:03:1a:38:16:59:7c:e2:c0:e8:54.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added 'localhost,192.168.235.10' (RSA) to the list of known hosts.
Last login: Sat Jun 20 03:08:07 2015 from 192.168.235.1
[root@root root]# exit
logout
Connection to localhost closed.
[root@localhost .ssh]# ll
total 16
-rw-r--r-- ? ?1 root ? ? root ? ? ? ? ?219 Jun 20 03:50 authorized_keys
-rw------- ? ?1 root ? ? root ? ? ? ? ?887 Jun 20 03:48 id_rsa
-rw-r--r-- ? ?1 root ? ? root ? ? ? ? ?219 Jun 20 03:48 id_rsa.pub
-rw-r--r-- ? ?1 root ? ? root ? ? ? ? ?234 Jun 20 03:51 known_hosts
[root@localhost .ssh]# ssh localhost
Last login: Sat Jun 20 03:51:38 2015 from localhost.localdomain
5.使用utraleidt编辑文件
配置core-site.xml、mapred-site.xml、hdfs-site.xml。
请参考：http://www.cnblogs.com/linjiqin/archive/2013/06/21/3147880.html