现有2台机器

1、服务器192.168.1.112
2、个人机192.168.1.110
要使110无需密码通过ssh登入112

步骤
1、创建密钥

miao@u32-192-168-1-110:~/.ssh$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter passphrase (empty for no passphrase): (忽略)
Enter same passphrase again: (忽略)
Your identification has been saved in /home/miao/.ssh/id_rsa.
Your public key has been saved in /home/miao/.ssh/id_rsa.pub.

2、复制公密到服务器

miao@u32-192-168-1-110:~/.ssh$ scp id_rsa.pub [email protected]:/home/miao/.ssh/192.168.1.110
[email protected]'s password:
id_rsa.pub                                                                   100%  404     0.4KB/s   00:00
miao@u32-192-168-1-110:~/.ssh$

3、添加公密到192.168.112的信任区域

miao@debian-192-168-1-112:~/.ssh$ cat 192.168.1.110 >> authorized_keys
miao@debian-192-168-1-112:~/.ssh$

4、启动ssh-agent 
如果ssh 192.168.112返回 Agent admitted failure to sign using the key 
ps -Af|agent查看有无ssh-agent有无运行，若没有

miao@u32-192-168-1-110:~/.ssh$ ssh-agent

5、添加id_rsa到ssh-agent

miao@u32-192-168-1-110:~/.ssh$ ssh-add id_rsa

6、完成

转自：http://www.jiangmiao.org/blog/559.html