Set OS X Server for remote-only administration I have a Mac Mini with OS X Server in another room with nothing attached but the network cable. I manage it remotely using Apple's Server and Remote Desktop.

Is it possible to disable "locally" using the machine. As to avoid:


Someone attaching a display and seeing my activity.
Someone taking over the server control by ending my Remote Desktop session.


Cheers
Unfortunately as long someone has physical access to hardware they can do pretty much anything with it. (depending upon they skills).

Your only semi safe solution would be to put it in a lock box.

Then set up password for log-in screen and password for idle (sleep mode).