[{ALLOW view All}]
[{ALLOW edit Authenticated}]

Links
* [http://freshtutorial.com/add-users-groups-change-password-linux-terminal/]
* [http://webtools.live2support.com/linux/passwd.php]

! Maintain 
Do not edit passwd and groups directly
{{{
groups markus				# show groups of a user
id markus				# show groups of user with ids
sudo usermod -g markus markus		# change primary group of an user
sudo usermod -aG groupname markus 	# add user to a group
sudo usermod -rG groupname markus 	# remove user from a group
sudo gpasswd -d markus groupname	# remove group of a auser
}}}

! /etc/passwd
* contains all Users
* Benutzer:Passwort:User-ID:Group-ID:Kommentar:home-Verzeichnis:Shell
* there is a shadow file under /etc/shadow

! /etc/group
* contains all groups

Editing the files above is not suggested, use following commands to maintain users and groups
{{{
who
who -a
users
w
cat /etc/passwd
cat /etc/group
usermod -G deploy,root root
usermod -a -G groupname username
usermod -d /path/to/new/homedir/ username
useradd
chown -R <user> *|change owner for whole subfolder
chmod <rights> <file>|x=1 w=2 r=4, oga = owner group all
chgrp
adduser username
passwd username
addgroup groupname
userdel username
deluser user group
groupdel groupname
vipw -s : Edit /etc/passwd file
vigr -s : Edit /etc/group file
}}}	

|chage|change user password expiry information 
{{{
chage -l username
chage -E 03/31/2014 -m 5 -M 90 -I 30 -W 14 username
}}}

Lock/Unlock user
|passwd -l <username>|Lock user
|passwd -u <username>|Unlock user
|passwd -a -S|Show list

List columns:
|1|login name\\
|2|locked password (L) / has no password (NP) usable password (P).\\
|3|date of the last password change\\
|4-7|password: minimum age, maximum age, warning period, inactivity period in days\\