From：http://blog.163.com/lgh_2002/blog/static/44017526201011333227161/
1、创建公钥和私钥
ligh@local-host$ ssh-keygen -t rsa Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key] Enter passphrase (empty for no passphrase): [Press enter key] Enter same passphrase again: [Pess enter key] Your identification has been saved in /home/jsmith/.ssh/id_rsa. Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub. The key fingerprint is: 33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9 ligh@local-host
2、使用ssh-copy-id将公钥复制到远程主机
ligh@local-host$ ssh-copy-id -i ~/.ssh/id_rsa.pub root@192.168.0.3 ligh@remote-host‘s password: Now try logging into the machine, with ―ssh ?remote-host‘‖, and check in: .ssh/authorized_keys to make sure we haven‘t added extra keys that you weren‘t expecting.
3、直接登录远程主机
ligh@local-host$ ssh remote-host Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2 ligh@remote-host$
ssh-keygen 创建公钥和密钥。
ssh-copy-id 把本地主机的公钥复制到远程主机的authorized_keys文件上。
ssh-copy-id 也会给远程主机的用户主目录（home）和~/.ssh, 和~/.ssh/authorized_keys设置合适的权限 。