Apple Workgroup Server 6150/66 - Manual (Page 20)

Physically isolating the system
It is important to note that even if software security features (such as password
protection or locking screen savers) are in use on the server, it is still possible
to disconnect peripheral devices—such as hard disks, which may contain
confidential information—from your server system. There is no better way to
protect hardware components than by physically isolating the server—locking
it either in a well-ventilated cabinet or in a room with controlled access.
Depending on your security needs, the nature of the data stored on the server
may warrant the effort.
Using a locking cable
As an alternative to isolating the system completely in an area of controlled
access, you can purchase a locking cable and attach it to your server. The back
panel has a built-in port for a locking cable. Follow the instructions supplied
with the locking cable to secure it to your server.
By itself, a locking cable cannot prevent unauthorized use of the server, but it
can prevent the server (and its peripheral devices if they are also secured by
locking cables) from being removed.
Security lock port
4 Chapter 1 / Setting Up Your Server