Mac mini as a server?

The Mac mini is designed to be used as an inexpensive desktop computer. However, the moment this computer was announced geeks started dreaming up other applications. The best fit seems to be as an in-dash computer for your car and there have been a few installations already.

Other solutions based around the mini are less ideal. Using it as a media center PC or DVR requires an external I/O box and either putting up with the limited laptop-sized hard drive or using an external FireWire drive.

In fact, the hard drive is the Mac mini's primary limitation. Being a 2.5" laptop drive, it is relatively slow and limited to 80Gb (as available from Apple.) In most other respects, the mini is actually an excellent computer, even beating Apple's other low-end systems in a number of performance tests.

Assuming that "you" have valid reasons for using MacOS X instead of Linux or (god-forbid) Windows, another potential use for the Mac mini is as a server. The mini's appropriateness for this role is dependent on exactly what you want to serve. With a minimal back-up option in place (such as a FireWire HD), the mini could be used for most basic services such e-mail, DNS, low-traffic web hosting, and basic non-multimedia file sharing for the home. However, the moment you exceed basic serving, the limitations of the mini's HD are likely to become glaringly obvious.

Of course, you could easily start adding external drives via the FireWire port, but the geekier amongst us would find that option too "inelegant," what with all the extra cables and everything.

So, is modifying the Mac mini a viable option? It is impossible to put a full-sized desktop drive into the Mac mini's case, so transplanting the mini's guts into a different case is required. Which brings us to this guy's Mac mini-based server. Although his server works, it's more of a proof-of-concept than something people should emulate because his total costs (which he doesn't openly state but I estimate as being more than $1,500 US) were high enough that a low-end PowerMac G5 with dual 250Gb drives would have been a smarter move and using a "pre-owned" PowerMac G4 instead of a Mac mini would have cost less than his mini-based rig. Either solution would have been better than what he ended up with.

While it may not be a smart move to put a mini in a tower case for use as a server, the question remains on whether it would be a good idea to build a low-end rack-mount server around a mini. Someone else has already shared their thoughts on a Mac mini rack-mount server. Considering that a low-end Xserve from Apple costs $2999US, this approach may actually make some sense. The Xserve does come with a MacOS X Server license, which costs $499 for the 10-client license (limit only applies to simultaneous file sharing) or $999 for the unlimited license, so you need to subtract whichever is appropriate for your needs. Still, that leaves you with at least $1500 to mod the mini into a 2U server (I don't think it'll be possible to get the mini in a 1U case.) This could easily be a viable option if you don't need the full power of the Xserve and I look forward to seeing if anyone tries this.

The other server aspect of the mini is its possible validity as an inexpensive Xgrid cluster node. In a gross over-simplification, the mini provides one-forth the processing power at one-sixth the price of the Xserve cluster node model. The big question would be whether the 100TX networking on the mini would totally invalidate it here, as 100TX seems completely inadequate as an interconnect. Assuming you were using an Xserve as the controller and connecting it to the nodes through one of these, it would be interesting to compare a 24 node mini cluster to a 4 node Xserve cluster. While you're at it, you might as well get some FireWire 400 hubs and try using that for an interconnect with the minis, just for shits and giggles.

Either way, the minis will probably get their butts kicked and I doubt anyone will ever conduct this experiment as it would cost about $33,000 for the hardware. Still, a 4 or 6 node cluster of Mac minis just might make a nice toy cluster to play with.

In conclusion, if you need a Mac server or a toy cluster and low cost is more important than performance the Mac mini may be a viable option for you.

2005-02-16 20:07 C&T