gpasswd command is used to administer the /etc/group and /etc/gshadow. As every group in Linux has administrators, members, and a password. It is an inherent security problem as more than one person is permitted to know the password. However, groups can perform co-operation between different users. This command assigns a user to a group with some security criteria. This command is called by a group administrator with a group name only which prompts for the new password of the group. System administrators can use the -A option to define group administrator(s) and -M option to define members. They have all rights of the group administrators and members.
gpasswd [option] group
Options: Here only -A and -M options can be combined.
- -a, –add : This option is used to add a user to the named group.
- -d, –delete : It is used to remove a user from the named group.
- -r, –remove-password : It is used to remove the password from the named group.
- -R, –restrict : This option will restrict the access to the named group.
- -A, –administrators : Set the list of administrative users.
- -M, –members : It set the list of group members.
- -h, –help : It displays the help message and exit.
$ sudo gpasswd -h
Example: Creating a group and adding a user to it. After that deleting the user.
- Adding a group named as geeks.
$ sudo groupadd geeks
- To display the created group with their id you can use:
- Now the group geeks is added so now execute command under to add the user to group geeks:
$ sudo gpasswd -a umang geeks
- Deleting the created user from group geeks.
$ sudo gpasswd -d umang geeks