补充更新：
centos更新openssh后不再支持ssh 第一版协议，所以第一版协议的配置信息也不需要了。
#这些配置信息都属于第一版协议，现在已经不需要了。 RSAAuthentication yes #指定公钥数据库文件 AuthorsizedKeysFile .ssh/authorized_keys
提示：
密钥会生成两个文件 [私钥 (id_rsa) 与公钥 (id_rsa.pub)] ，建议设置并牢记passphrase密码短语。
Linux：
ssh-keygen -t rsa
Windows：SecurCRT/Xshell/PuTTY
SSH-2 RSA 2048
一、创建密钥
#生成SSH密钥对 ssh-keygen -t rsa Generating public/private rsa key pair. #建议直接回车使用默认路径 Enter file in which to save the key (/root/.ssh/id_rsa): #输入密码短语（留空则直接回车） Enter passphrase (empty for no passphrase): #重复密码短语 Enter same passphrase again: Your identification has been saved in /root/.ssh/id_rsa. Your public key has been saved in /root/.ssh/id_rsa.pub. The key fingerprint is: aa:8b:61:13:38:ad:b5:49:ca:51:45:b9:77:e1:97:e1 [email protected] The key's randomart image is: +--[ RSA 2048]----+ | .o. | | .. . . | | . . . o o | | o. . . o E | |o.= . S . | |.*.+ . | |o.* . | | . + . | | . o. | +-----------------+
二、复制密钥对
#复制公钥到无密码登录的服务器上,22端口改变可以使用下面的命令
#ssh-copy-id -i ~/.ssh/id_rsa.pub “-p 10022 user@server”
ssh-copy-id -i ~/.ssh/id_rsa.pub [email protected]
或者也可以手动在服务器端建立目录和authorized_keys，注意修改权限。
也或者, you can paste in the keys using SSH （下面是一行命令）
cat ~/.ssh/id_rsa.pub | ssh [email protected] "mkdir -p ~/.ssh && cat >> ~/.ssh/authorized_keys"
No matter which command you chose, you should see something like:
The authenticity of host ‘12.34.56.78 (12.34.56.78)’ can’t be established.
RSA key fingerprint is b1:2d:33:67:ce:35:4d:5f:f3:a8:cd:c0:c4:48:86:12.
Are you sure you want to continue connecting (yes/no)? yes
Warning: Permanently added ‘12.34.56.78’ (RSA) to the list of known hosts.
[email protected]’s password:
Now try logging into the machine, with “ssh ‘[email protected]′”, and check in:
~/.ssh/authorized_keys
to make sure we haven’t added extra keys that you weren’t expecting.
三、修改SSH配置文件 （测试效果 成功）
提示:
1、RSAAuthentication yes;这个配置好像没有了
2、PermitRootLogin yes; 表示 root 用户 可以 通过 SSH 登录：不是一定要修改的。
#编辑sshd_config文件 vim /etc/ssh/sshd_config #禁用密码验证 PasswordAuthentication no #启用密钥验证 RSAAuthentication yes PubkeyAuthentication yes #指定公钥数据库文件 AuthorsizedKeysFile .ssh/authorized_keys
其实可以直接用命令行 来修改 ssh 的配置值。
sed -i "s/^PasswordAuthentication.*/PasswordAuthentication no/g" /etc/ssh/sshd_config sed -i "s/^#RSAAuthentication.*/RSAAuthentication yes/g" /etc/ssh/sshd_config sed -i "s/^#PubkeyAuthentication.*/PubkeyAuthentication yes/g" /etc/ssh/sshd_config sed -i "s/^#AuthorizedKeysFile.*/AuthorizedKeysFile .ssh\/authorized_keys/g" /etc/ssh/sshd_config