1.生成秘钥，遇到提示直接敲回车即可
1 [root@localhost ~]# ssh-keygen
2 Generating public/private rsa key pair.
3 Enter file in which to save the key (/root/.ssh/id_rsa):
4 Enter passphrase (empty for no passphrase):
5 Enter same passphrase again:
6 Your identification has been saved in /root/.ssh/id_rsa.
7 Your public key has been saved in /root/.ssh/id_rsa.pub.
8 The key fingerprint is:
9 SHA256:/gGrlDJN5euMS5aai5feBkEI/0WjEnzPzx1xGtdkKG4 root@localhost.localdomain
10 The key's randomart image is:
11 +---[RSA 2048]----+
12 |.o.. o +o |
13 | .o.oo . + +.. |
14 | oo.o. .. B |
15 | o..oo E |
16 | ...oSo . |
17 | .o +o+. |
18 | ooB + . |
19 | .oX.= . . |
20 | .o=o=.o . |
21 +----[SHA256]-----+
22 [root@localhost ~]# ls ~/.ssh/
23 id_rsa id_rsa.pub known_hosts
24 [root@localhost ~]#
2.解决找不到 .ssh 目录
如果在上面生成秘钥后，执行 cd ~/.ssh 找不到 .ssh 目录，是因为没有使用 ssh 登录过，使用 ssh 登录一下即可生成 .ssh 目录，之后再重新执行 ssh-keygen 生成秘钥即可
1 [root@localhost ~]# ssh localhost
2 The authenticity of host 'localhost (::1)' can't be established.
3 ECDSA key fingerprint is SHA256:DYd7538oOsqpIIDTs01C3G4S6PRE7msA91yUgk9Dzxk.
4 ECDSA key fingerprint is MD5:88:80:21:03:b2:52:6b:06:ff:c7:3b:d5:2d:47:c9:ad.
5 Are you sure you want to continue connecting (yes/no)? yes
6 Warning: Permanently added 'localhost' (ECDSA) to the list of known hosts.
7 root@localhost's password:
8 Last login: Fri Oct 26 16:15:57 2018 from localhost
9 [root@localhost ~]# ls ~/.ssh/
10 known_hosts
11 [root@localhost ~]# exit
12 登出
13 Connection to localhost closed.
14 [root@localhost ~]#
3.在服务器上安装公钥
[root@ecs-326c-0001 .ssh]# cat id_rsa.pub >> authorized_keys
4.为了确保连接成功，需要设置文件权限
[root@ecs-326c-0001 .ssh]# chmod 600 authorized_keys
[root@ecs-326c-0001 .ssh]# chmod 700 ~/.ssh
5.设置ssh，打开秘钥登录功能
[root@ecs-326c-0001 .ssh]# vim /etc/ssh/sshd_config
去掉注释#
RSAAuthentication yes
PubkeyAuthentication yes
6.重启ssh服务
[root@ecs-326c-0001 ~]# systemctl restart sshd
7.拷贝私钥到PC端，使用软件导入秘钥，然后测试登录
8.秘钥测试登录成功之后，可以禁用使用密码登录，提高服务器的安全性
[root@ecs-326c-0001 .ssh]# vim /etc/ssh/sshd_config
修改为no
PasswordAuthentication no