ssh 无密码登录详解程序员

:~> ssh-keygen -t rsa 
Generating public/private rsa key pair. 
Enter file in which to save the key (/home/a/.ssh/id_rsa):  
Created directory '/home/a/.ssh'. 
Enter passphrase (empty for no passphrase):  
Enter same passphrase again:  
Your identification has been saved in /home/a/.ssh/id_rsa. 
Your public key has been saved in /home/a/.ssh/id_rsa.pub. 
The key fingerprint is: 
3e:4f:05:79:3a:9f:96:7c:3b:ad:e9:58:37:bc:37:e4 

:~> ssh  mkdir -p .ssh 
's password:

:~> cat .ssh/id_rsa.pub | ssh  'cat >> .ssh/authorized_keys2' 
's password:
:~> sudo chmod 700 ~/.ssh
:~> sudo chmod 640 ~/.ssh/authorized_keys2

:~> ssh  hostname 
B