Add & Delete Groups in Linux

We can easily add/delete groups in Linux using `groupadd`, `groupdel` commands.

Add/Delete Groups

# Add a group
groupadd <group>

# Delete a group
groupdel <group>

Add User to Group

# -a: Append the user to the specific group
# -G: Group
usermod -a -G <group> <user>

# Change user's primary group
# -g: GID
usermod -g <group> <user>

Sudo Group

Ussers who belong to sudo group can execute commands with sudo. To add a user to the sudo group, run the following command.

usermod -a -G sudo <user>

After that, we can check the result.

# Switch to target user
su <user>
# List the user's privileges.
sudo -l

List Groups

We can see groups exist in Linux using the following commands.

cat /etc/group

groups
# List groups where the specific user in
groups <user>