1.新建用户$ adduser xxuser

2.新建ssh目录$ mkdir /home/xxuser/.ssh

3.把公钥添加到/home/xxuser/.ssh/authorized_keys这个文件里

4.chmod 600 /home/xxuser/.ssh/authorized_keys

5.chmod 700 /home/xxuser/.ssh

6.chown -R xxuser:xxuser /home/xxuser/.ssh

7.修改/etc/ssh/sshd_config文件最下方

PermitRootLogin no
PasswordAuthentication no

8.重启 ssh 服务 /etc/init.d/ssh reload