xxx is not in the sudoers file. This incident will be reported

1. Switch to root Under the user

2. add to sudo Write permission of file , The order is :

chmod u+w /etc/sudoers

3. edit sudoers file

vi /etc/sudoers
Find this line root     ALL=(ALL)    ALL, Add it below xxx ALL=(ALL) ALL ( there xxx It's your user name )

ps: Here you can sudoers Add any of the following four lines
youuser ALL=(ALL) ALL
%youuser ALL=(ALL) ALL
youuser ALL=(ALL) NOPASSWD: ALL
%youuser ALL=(ALL) NOPASSWD: ALL

first line : Allow users youuser perform sudo command ( You need to enter a password ).
The second line : Allow user groups youuser User execution inside sudo command ( You need to enter a password ).
The third line : Allow users youuser perform sudo command , And do not enter the password when executing .
In the fourth row : Allow user groups youuser User execution inside sudo command , And do not enter the password when executing .

4. revoke sudoers File write permission , command :

chmod u-w /etc/sudoers

So ordinary users can use sudo 了