Overview of adding sudo permission groups to ubuntu users

Overview of adding sudo permission groups to ubuntu users

groupadd -g 1005 dev

Add a user group and set the gid to 1005.

groupdel dev 

Delete user group dev

Add User

adduser mike

The system will automatically prompt you to enter the password.

useradd  simael -u 600 -g 1005 -s /bin/bash

-U specifies uid (system retains 0-499)-g specifies user group-s specifies shell used
Then

passwd simael 

Set password for user

Delete a user

userdel mike

If you are prompted that you have logged in and logged out of the user through skill

skill -KILL -u mike

Cancel mike user

View all users and user groups:

cat /etc/passwdcat /etc/group

Add permissions for users to use the sudo command

Add the write permission for the sudo file. The command is:

chmod u+w /etc/sudoers

Edit sudoers file

vi /etc/sudoers

Find this line of root ALL = (ALL) ALL, add xxx ALL = (ALL) ALL under it (here xxx is your user name)

Ps: You can add any of the following four lines to sudoers:

youuser            ALL=(ALL)                ALL%youuser           ALL=(ALL)                ALLyouuser            ALL=(ALL)                NOPASSWD: ALL%youuser           ALL=(ALL)                NOPASSWD: ALL

Line 1: allow the user youuser to execute the sudo command (password required ).
Line 2: Allow users in the user group youuser to execute the sudo command (password required ).
Row 3: allows the user youuser to execute the sudo command without entering the password during execution.
Row 4: Allow users in the user group youuser to execute the sudo command without entering the password during execution.

4. revoke the sudoers file write permission by running the following command:

chmod u-w /etc/sudoers

In this way, general users can use sudo.
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Id-u: displays the uid of the current user

Id-g displays the current user's gid

You can also view which group the user belongs:

View the content in/etc/passwd. The first item in each line is groupID, and the fifth item is Usr ID Info, which is similar to the group name. You can use vim, grep, and other methods to quickly find the row of a specified user. Familiar with awk, you can also write a script.

grep mike /etc/passwd|awk -F: '{ print $5}'