0、linux运行环境

 

1)操作系统版本

CentOS Linux release 7.2.1511 (Core) 

2)机器说明

IP地址

机器名(hostname)

172.24.5.173

bgs-5p173-wangwenting

172.24.5.174

bgs-5p174-wangwenting

172.24.5.175

bgs-5p175-wangwenting

 在集群模式下,本文默认 172.24.5.173 为集群中的 master, 172.24.5.174 和 172.24.5.175 为集群中的 slave。

3)同步时间

在三个机器上分别运行 data 命令同步时间,精确到秒

xx:xx:xx 表示当前你要设置的时间格式和具体时间。
[root@bgs-5p173-wangwenting ~]# data -s xx:xx:xx

4)建立账号

在三个机器上都建立hadoop账户,密码和账号一样

[root@bgs-5p173-wangwenting ~]# useradd -d /opt/hadoop hadoop
[root@bgs-5p173-wangwenting ~]# passwd hadoop


给 hadoop 用户分别加上 sudo 权限

# vim /etc/sudoers

root        ALL=(ALL) ALL
hadoop      ALL=(ALL) ALL

5)建立账户后,需要对 hadoop 账户实现无密码 ssh 登陆的功能 。

[root@bgs-5p173-wangwenting ~]$ su hadoop
生成密钥,一直按enter键:
[hadoop@bgs-5p173-wangwenting ~]$ ssh-keygen -t rsa
将秘钥发送到其他机器上:
[hadoop@bgs-5p173-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p173-wangwenting
[hadoop@bgs-5p173-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p174-wangwenting
[hadoop@bgs-5p173-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p175-wangwenting
验证是否免秘钥登录成功:
[hadoop@bgs-5p173-wangwenting ~]$ ssh 172.24.5.173
[hadoop@bgs-5p173-wangwenting ~]$ ssh 172.24.5.174
[hadoop@bgs-5p173-wangwenting ~]$ ssh 172.24.5.175
如果能登录且不用输密码,则172.24.5.173可以免密码登录另外两台机器。
  
同理要想172.24.5.174可以免密码登录另外两台机器需要执行以下操作:
[hadoop@bgs-5p174-wangwenting ~]$ ssh-keygen -t rsa
将秘钥发送到其他机器上:
[hadoop@bgs-5p174-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p173-wangwenting
[hadoop@bgs-5p174-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p174-wangwenting
[hadoop@bgs-5p174-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p175-wangwenting
验证是否免秘钥登录成功:
[hadoop@bgs-5p174-wangwenting ~]$ ssh 172.24.5.173
[hadoop@bgs-5p174-wangwenting ~]$ ssh 172.24.5.174
[hadoop@bgs-5p174-wangwenting ~]$ ssh 172.24.5.175
如果能登录且不用输密码,则172.24.5.174可以免密码登录另外两台机器。
  
同理要想172.24.5.175可以免密码登录另外两台机器需要执行以下操作:
[hadoop@bgs-5p175-wangwenting ~]$ ssh-keygen -t rsa
将秘钥发送到其他机器上:
[hadoop@bgs-5p175-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p173-wangwenting
[hadoop@bgs-5p175-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p174-wangwenting
[hadoop@bgs-5p175-wangwenting ~]$ ssh-copy-id -i ~/.ssh/id_rsa.pub hadoop@bgs-5p175-wangwenting
验证是否免秘钥登录成功:
[hadoop@bgs-5p175-wangwenting ~]$ ssh 172.24.5.173
[hadoop@bgs-5p175-wangwenting ~]$ ssh 172.24.5.174
[hadoop@bgs-5p175-wangwenting ~]$ ssh 172.24.5.175
如果能登录且不用输密码,则172.24.5.175可以免密码登录另外两台机器。
  
最终:三台机器之间可以免密码互相登录。
原文地址:https://www.cnblogs.com/wyl9527/p/6550207.html