gpasswd

Administer /etc/group and /etc/gshadow. More information: https://manned.org/gpasswd.

• Define group administrators:

sudo gpasswd -A {{user1,user2}} {{group}}

• Set the list of group members:

sudo gpasswd -M {{user1,user2}} {{group}}

• Create a password for the named group:

gpasswd {{group}}

• Add a user to the named group:

gpasswd -a {{user}} {{group}}

• Remove a user from the named group:

gpasswd -d {{user}} {{group}}