CentOS system Add/Remove user and user group examples

1, Build Users:

AddUser PHPQ//New PHPQ User
passwd PHPQ//Set Password to PHPQ user

2, the establishment of the Working Group
Groupadd test//New test Workgroup

3, new users to increase the team at the same time
USERADD-G test PHPQ//new PHPQ user and add to test workgroup

Note:: The shell used by the group-D home Directory-S for-G

4, to the existing user to increase the Working group

USERMOD-G groupname username

Or: Gpasswd-a user Group

5, temporary shutdown: In the/etc/shadow file belongs to the user's line of the second field (password) before adding * on it. To restore the user, remove the * can.

Or, use the following command to close the user account:

passwd peter–l

Re-release:

passwd Peter–u

6. Permanently delete user account

Userdel Peter

Groupdel Peter

Usermod–g Peter Peter (forcibly deletes all files and subdirectories under this user's home directory and home directory)

7, remove users from the group

Edit/etc/group Find GROUP1 line, delete A or use command gpasswd-d a group

8. Display user Information

ID User
cat/etc/passwd

Add: Ways to view users and user groups

User list file:/etc/passwd
User group list file:/etc/group

See which users are in the system: cut-d:-F 1/ETC/PASSWD
View users who can log on to the system: CAT/ETC/PASSWD | Grep-v/sbin/nologin | Cut-d:-F 1
View user actions: W command (requires root permission)
View a User: W user name
View Logged-in users: Who
View user logon history: Last