Users and Groups in Linux : Create, List, Add, Edit, Assign, and Delete

Описание: How to Create, List, Add, Edit, Assign and change user groups, and Delete Users and Groups in Linux

Commands used:

1. list users
show current user
#users
list all users
#cat /etc/passwd or #getent passwd

2. list groups
show groups for current user
#groups
show groups for a user
#groups username
list all groups
#cat /etc/group or #getent group

3. Create a New User
Create a New User
#useradd username
this command will create user and a group will also created for the new user with the same name
Create a New User and Assign a Group in one command
#useradd -G groupname username
or
#useradd -G group1,group2,group3 username

4. change user password or set password for the new user
#passwd username

5. add new group
#groupadd newgroup

6. Add existing User to a Group
add a User to a Group
#usermod -a -G group username
add a User to Multiple Groups
#usermod -a -G group1,group2,group3 username

7. Removing user from group
#gpasswd -d username group

8. Change User Primary Group
#usermod -g group user
Note: -g lowercase to assign user primary group

9. delete groups
#groupdel groupname

10. delete user
#userdel username
#userdel -r username
Note: -r option to remove user's home directory and the user's mail spool