Ken Collins built a full fledged NOC using Mac Mini’s.

I have 3 Mac Mini’s in our data center, running along side 3 Apple Xserves, and a 4th here on my desktop for development.

They are amazing little machines, and when tuned correctly, hum along nicely for just about any simple task.

Here are a few tips, based on my experience:

• Edit the /etc/hostconfig file and use free utilities, to disable services like Crash Reports, Printing Services, Spotlight and Dashboard. I managed to get the core system to use less than 170 MB of memory.

• Dump Apache for a light weight web server. Lighttpd is my preference, it is powerful, stunningly fast, and simple to configure.

• Use memory caching to speed up dynamic content, using FastCGI or SCGI whenever possible. This will require you to rebuild PHP for FastCGI.

• Build a true chroot ssh environment

• Disable SSHv1 in /etc/sshd_config

• Use scp with certificates to automate backup to a separate server. These are consumer machines so storing data on a separate partition does nothing.

• Build and install all essential tools outside the paths known by Apple’s Software Update. I have seen Apple’s Software Update open up entire servers to hacks.

The secure.log will fill up with hack attempts the moment you put the machine on line, and you will be hacked, unless you take precautions beyond setting a few preferences in the OS X System Preferences.

Make sure you put the Mini behind an industrial strength firewall. The OS X firewall is decent, but if your data center does not provide ACL service, find one that does.

This blog is running on a Mac Mini, along with numerous other sites.