Linux下配置免密登录！

ssh-keygen  产生公钥与私钥对.

ssh-copy-id 将本机的公钥复制到远程机器的authorized_keys文件中，ssh-copy-id也能让你有到远程机器的home, ~./ssh , 和 ~/.ssh/authorized_keys的权利

第一步:在本地机器上使用ssh-keygen产生公钥私钥对

1. jsmith@local-host$ [Note: You are on local-host here]
2. jsmith@local-host$ ssh-keygen
3. Generating public/private rsa key pair.
4. Enter file in which to save the key (/home/jsmith/.ssh/id_rsa):[Enter key]
5. Enter passphrase (empty for no passphrase): [Press enter key]
6. Enter same passphrase again: [Pess enter key]
7. Your identification has been saved in /home/jsmith/.ssh/id_rsa.
8. Your public key has been saved in /home/jsmith/.ssh/id_rsa.pub.
9. The key fingerprint is:
10. 33:b3:fe:af:95:95:18:11:31:d5:de:96:2f:f2:35:f9 jsmith@local-host

第二步:用ssh-copy-id将公钥复制到远程机器中

1. jsmith@local-host$ ssh-copy-id -i ~/.ssh/id_rsa.pub remote-host
2. jsmith@remote-host's password:
3. Now try logging into the machine, with "ssh 'remote-host'", and check in:
4. .ssh/authorized_keys
5. to make sure we haven't added extra keys that you weren't expecting.

注意: ssh-copy-id 将key写到远程机器的 ~/ .ssh/authorized_key.文件中

第三步: 登录到远程机器不用输入密码

1. jsmith@local-host$ ssh remote-host
2. Last login: Sun Nov 16 17:22:33 2008 from 192.168.1.2
3. [Note: SSH did not ask for password.]
4. jsmith@remote-host$ [Note: You are on remote-host here]

另外：

1. ssh-copy-id -u wyz -i ~/.ssh/id_rsa.pub wyz@remote_host

上述是给wyz用户赋予无密码登陆的权利