useradd dgb8901

passwd dgb8901 # 回车

New password: 
BAD PASSWORD: The password fails the dictionary check - it is based on a dictionary word
Retype new password: 
passwd: all authentication tokens updated successfully.

ls -l /etc/sudoers # 查看 /etc/sudoers 文件权限
chmod 777 /etc/sudoers # 一般 /etc/sudoers 是只读的，修将其改为可写权限

## Allow root to run any commands anywhere 
root	ALL=(ALL) 	ALL
dgb8901    ALL=(ALL)       ALL

chmod 440 /etc/sudoers

su - dgb8901