adduser 123
passwd 123
;;添加账号并设置密码

nano /etc/passwd
123:x:500:500:keaising:/home/keaising:/bin/bash
修改后
123:x:0:500:keaising:/home/keaising:/bin/bash
把500改为0 保存

nano /etc/ssh/sshd_config
#PermitRootLogin yes
改为
PermitRootLogin no
;限制root登陆