I used the command visudo -f /etc/sudoers to edit the sudoers file.
How do I make a group be able to run the shutdown command without supplying password?
You can often find an example of something like that in the sudoers
file like looking at the %wheel
group. If a "username" field starts with %
it's treated as a group name. So you could do something like
%<group> ALL=NOPASSWD: /sbin/shutdown
To allow any user in <group>
on any host using that sudoers
to run /sbin/shutdown
without a password. Bear in mind, if there are multiple rules that match, it is the last rule that will "win."