Manage Linux Users

A Friendly Way to Add New Users

For Debian and Ubuntu:

# add a new user tom
sudo adduser tom

# add tom to sudo group
sudo adduser tom sudo

# delete the user tom
sudo deluser tom

The default config should ask you to set the password for the user. After you set the first password for tom, you can use sudo passwd -e tom to expire the password and force tom to set a new password upon login.

Manage Groups

# add a new group called cert
sudo groupadd cert

Add Existing User to a Group

# add existing user tom to group sudo
sudo gpasswd -a tom sudo
# or
sudo usermod -aG sudo tom

# remove existing user tom from group sudo
sudo gpasswd -d tom sudo

Low Level Utilities

Other than the friendly way to manage user, there are also low level utilities to manage users, notice any different below?

# low level utilities
useradd
userdel

# Debian/Ubuntu friendly front ends
adduser
deluser