the mac mini as a personal server

A large number of people on the internets are craving the new Mac Mini – the $500 “headless mac”, unveiled at Macworld two days ago – trying to figure out what the business implications are and the role the Mini might play as a home (or car!) based entertainment platform.
The general consensus is that the Mac Mini is the camel’s nose under the tent, a way for apple to rapidly gain entry into the mass market computing space.
One application for a small computer like the Mini is to use it as a personal server (PS). The need for such a device is driven by the increasing size and importance of the digital data that consumers are archiving and sharing, and the trend towards laptop-only, wireless households (which lack the option of using the family desktop PC as a de-facto file server).

The nascent market for Personal Servers is currently split between the Buffalo Linkstation and the Mirra Personal Server, and some also rans from Netgear and Linksys). The Mac Mini could be a compelling new entry to this market.
A consumer personal server (PS) should support the following applications:
Backups: the need for consumers to have some kind of backup strategy is being driven by digital cameras. Losing 5 years of family memories to a hard drive failure is unacceptable, and backing up to CDs or DVDs ends up being a time-consuming chore that increases clutter. Backing up to disk over the home network is the only halfway decent solution.
File Server: media files (in particular music files) need to be accessible from every PC in a house. Especially in laptop-only houses, this means that a file server of some kind is needed. Current consumer offerings are pushing some kind of media PC solution that provides DVR, but consumers don’t seem to want PCs in their living room. Media clients like the
slimdevices squeezebox provide a compelling living-room alternative to the MediaPC, but require a file server of some kind to be running in order to function.
FTP server: A personal ftp server allows consumers to easily share such large video files with friends and family. This will become as big a deal 2 years from now as digital still photography sharing is today. I’m already using two linkstations to provide a two-way large file transport system (for audio and video files) between my US office and my international office.
P2P Client: Running a file sharing client like BitTorrent from a laptop has severe performance and security issues (constant hard drive/CPU activity, heavy wifi traffic, and concerns about viruses / spyware). Running a bittorrent client from a dedicated machine that a)is directly connected to the network by Ethernet, and b)runs a non-Windows OS solves these problems.
Form Factor: Basically, a PS has to be router-sized (to fit in the existing home network). Even a shuttle-based PC is really too big for the shoebox or bookshelf that most people keep their network equipment in.
Operating System/Software bundle: A personal server should run a secure operating system if it will be used for FTP/P2P applications, and it must ship with the operating system and relevant application software preinstalled.
How does the Mini stack up against the Mirra and the Linkstation?

LinkStation Mirra Mini Advantage
Price $280 $400 $500 Linkstation
Backup Support software provided not great: can use 3rd party software excellent can use third party software Mirra
File Server Support excellent not supported may be compatibility issues with Windows machines? Linkstation
FTP Server Support excellent not supported excellent Linkstation / Mini
P2P Client Support not supported not supported use any mac bittorrent client Mini
Hard drive space 160 Gb 80 Gb 40 Gb LinkStation
Computing Power 200 Mhz PowerPC, 64 Mb RAM ? 1.25 Ghz PowerPC, 256 Mb RAM Mini
Power Consumption 17 Watts 40 Watts 85 Watts Linkstation
OS Linux Linux OSX/FreeBSD Mini
Form Factor router (internal power supply) minitower router (external power supply) LinkStation
Expandability USB HDs/Printers none any USB peripherals Mini

The Mini is the wrong hardware configuration for a personal server: the processor speed, RAM, and graphics capabilities (and resulting power consumption) are in excess of what is needed, and the hard drive is inadequate, forcing users to expand almost immediately with a USB external drive.
However, it obviously has more flexibility than any other option presented above: you can install arbitrary software on it without voiding your warrantee using hacks.
Well-heeled users who are looking for a full-fledged personal server that can run arbitrary software (like P2P clients or a web server) should consider the Mini: at $500, it’s the cheapest TRUE small-form-factor computer out there, and should fit nicely into a home network. People complaining about the price are comparing it to boxy PCs, not to the true form factor equivalent, which is more like a very pricey Hush silent PC When compared to true peers the Mac Mini is a hardware bargain. Users who need a desktop computer that can also be used as a PS are suitable candidates for buying a Mac Mini: users who are strictly looking for a file server and backup solution should probably stick with the Linkstation.
The Mirra offers neither expandability nor an appropriate form factor, so it is only appropriate for users whose only reason for getting a PS is backup.
UNIX enthusiasts who don’t mind getting their hands dirty should also consider the Buffalo KuroBox, a full linux server with the same form factor as the Linkstation, or the Linksys NSLU2, both of which have substantial developer communities.
The Linkstation remains the PS to beat: if it shipped with better (Mirra-quality) backup software and a p2p client, it would be an very cheap, very good personal server. But for situations where you need a “real” computer as part of your personal network, the Mini is an interesting candidate.
Look for a more suitable PS offering from Apple in the future. In the words of Merill Lynch
A 200GB Apple server at a reasonable price and possibly with PVR technology could be Apple’s next category killer
For more on Apple Personal Server stuff, Nicest of the Damned has some fine articles on the topic, some going back years.
Update (1/20/05). Mike Clark has a nice piece suggesting using the mac mini as a build server. The idea is to automatically detect mac integration issues as early as possible. Not a bad idea! Of course, in India (where my dev team is), a mac mini probably sells for more like 2000$ than 500$. But hardware costs in South Asia are a topic for another post. ;->
Update (2/4/05). A nice how-to piece on on setting up your mac mini as an _outward_ facing server. Slightly different from the personal server concept what I’m talking about in this piece, but a nice read that covers all the gotchas (firewall, dns, etc).