linux远程登录免password

如果希望从ServerA免输入passwd ssh到ServerB，先在ServerA上执行:

ssh-keygen -t rsa

例如：连续回车即可

hanqf@localhost:~$ ssh-keygen -t rsa
Generating public/private rsa key pair.
Enter file in which to save the key (/home/hanqf/.ssh/id_rsa):
Created directory '/home/hanqf/.ssh'.
Enter passphrase (empty for no passphrase):
Enter same passphrase again:
Your identification has been saved in /home/hanqf/.ssh/id_rsa.
Your public key has been saved in /home/hanqf/.ssh/id_rsa.pub.
The key fingerprint is:
d5:5a:63:3d:e7:09:d9:34:d5:2b:55:b5:a8:d8:7d:b9 hanqf@localhost

结果会在当前用户的家目录下的.ssh目录下面生成两个文件id_rsa.pub和id_rsa

把id_rsa.pub拷贝到ServerB的用户目录下的.ssh目录下的authorized_keys文件中，

如果ServerB下还没有这个文件，可以执行下面这个命令。

scp id_rsa.pub ServerB:~/.ssh/authorized_keys

例如：

hanqf@localhost:scp id_rsa.pub develop@192.168.1.219:~/.ssh/authorized_keys

develop@192.168.1.219's password:

如果ServerB已经有了该文件，请执行下面的命令把SeverA的id_rsa.pub的内容添加到该文件中。

scp id_rsa.pub ServerB:~/.ssh/ServerA_rsa.pub
cat ServerA_rsa.pub >> authorized_keys

hanqf@localhost:scp id_rsa.pub develop@192.168.1.219:~/.ssh/192.168.1.219_rsa.pub

develop@192.168.1.219's password:

hanqf@localhost:ssh develop@192.168.1.219

develop@192.168.1.219's password:

develop@localhost: cat 192.168.1.219_rsa.pub >> authorized_keys

测试一下儿：

hanqf@localhost:ssh develop@192.168.1.219

Last login:Wed May 13 14:41:43 2009 from 192.168.0.66

develop@localhost:

如果想从ServerB无password登录到ServerA，请把上述过程反向操作一遍。