Managing Users & Groups

Creating & Modifying Accounts

Command	Purpose
`useradd -m -s /bin/bash alice`	Create user with home + shell
`passwd alice`	Set/change password
`usermod -aG sudo alice`	Append to a supplementary group
`usermod -L` / `-U`	Lock / unlock account
`userdel -r alice`	Delete user and home
`groupadd devs`	Create group
`groupdel devs`	Delete group
`id alice`	Show UID/GID/groups
`chage -l alice`	Password ageing info

$ useradd -m -s /bin/bash alice && id alice
uid=1001(alice) gid=1001(alice) groups=1001(alice)

Exam trap: Always use usermod -aG (append). Plain usermod -G replaces all supplementary groups and will silently remove the user from others.