User Management – How to Change Primary Group

user-management

I want to remove user pserver from the group apache.

#deluser pserver apache
/usr/sbin/deluser: You may not remove the user from their primary group.

Now I want to add a new primary group, so I ran the following;

#usermod -G pserver pserver

Which returned the following:

pserver` is now in group `pserver

#groups pserver
pserver : apache pserver

Now I want to remove the user again from group apache, but I get same error again. How can I delete pserver from the primary group apache?

Best Answer

The usermod option -G adds supplementary groups. You want option -g to change the primary group. I.e. your command should have been:

# usermod -g pserver pserver

Note, this will also change group ownership of files in the home directory, but not elsewhere.

More generally, the syntax for changing user 'user' to have primary group 'group' is:

# usermod -g group user