[CentOS] How to restrict reboot/poweroff from non-admins?

[Phil Schaffner]

Timo Neuvonen wrote on 03/28/2012 09:17 AM:
> I just noticed that CentOS (6.2) by default allows any user to
> reboot/poweroff system without any admin rights, or without any further
> questions, if using commands 'reboot' or 'poweroff'. But 'shutdown' still
> requires admin rights.
>
> What is the preferred way to restrict any regular user from rebooting /
> powering off the system (by accident)?
>
> IMHO, sudo should be required for this purpose (at least in a system with
> shared remote access from multiple users, single-user laptops etc may be a
> different case)
>

OUCH! This seems to qualify as a CentOS bug.  I confirm that a normal 
user can reboot or poweroff the system on 6.2.  On RHEL:

$ rpm -qa redhat-release\*
redhat-release-server-6Server-6.2.0.3.el6.x86_64
$ poweroff
poweroff: Need to be root
$ reboot
reboot: Need to be root

Phil