Securing a rack in a shared server room

Sounds like quite the argument for not using a shared server room facility, but what you can/should do to fairly easily avoid this problem is:

1. Physical access controls on the server room.
   • Could be as simple as a good lock and a key, an RFID badge, or even biometric scanners, but make it something.
   • If you prevent who has access to the room with a good door, decent lock(s), and control over who has the key/badge/biometric clearance to get in, you drastically limit who'll even be in a position to be able to steal your gear.
2. Audio/video surveillance (AKA security cameras).
   • People are much less likely to try to steal something when there's a camera staring them down the whole time.
3. A monitoring system.
   • Get a monitoring system for your gear, so if someone unplugs everything, all the alarms and alerts go off, and everyone starts looking for what's wrong.
     • Couple with a remotely viewable security camera or cameras, and if such a thing happens, you'll be able to know what's going on nearly instantly.
     • Something fairly easy to do, that you should be doing for other reasons anyway, honestly.
4. Physical access controls on the rack and gear in it.
   • Generally, the locks that come on server racks or are used to lock servers into a rack aren't going to stop a determined attacker, but if you're doing the other things right, someone will notice and stop a stranger taking a crowbar to your rack to steal what's inside.
5. Physically secure the rack.
   • Assuming you're in an actual server room or data-center environment you can get cable locks (or even use a long chain and a padlock) you attach to the rack, and run under the raised flooring to prevent the rack from being wheeled away.
     • (EDIT): If you're not in a "real" server room/data-center environment, then yes, this would mean chaining the rack to some piece of infrastructure. It's what you're effectively doing with a chain or cable lock under the floor anyhow (securing the rack to the sub-floor infrastructure your tiles sit on).

Speak to Rittal, they make racks that can be bolted to the tiles or floor under a rack plus lots of customisable anti-intruder electronics such as vibration detection, remote door opening/alerting and internal cameras. We have these and they're great, not even too expensive either.