Not to discount your expertise in any way, shape or form here...
Given that even DOS-based systems can screw up horribly if you turn
them off at just the right time (Linux systems will usually survive
random power shutoffs too, especially if you stick a -y in the fsck
line in the bootup scripts -- the main difference is that DOS will
boot up with the filesystem still trashed and proceed to grind), you
may want to think about this more carefully.
There are a couple of ways by which Linux can, indeed, be power-off
safe, and I mean truly safe.
The most obvious way is to hook up a small UPS and run powerd. The
UPS keeps the system alive long enough to shut down; powerd handles
the controlled shutdown based on a signal received from the UPS.
There are, or at least used to be, small UPSes (2-3 minutes duration)
that fit inside a PC power supply and operate on the DC side (no need
for an inverter); conventional small UPSes are quite cheap these days.
On a software level, the key to running Linux power-down-safe involves
the following rules:
a) Any local, persistent filesystem should be mounted read-only.
b) Use a RAMdisk for mutable data you don't care about, and
re-initialize it from readonly media on boot; for data you
*do* care about saving use a remote server.
We have a couple of Linux boxen which act as routers here, mainly
since we can get pretty beefy systems for 1/10 the price of a Cisco.
These boxen keep their entire filesystem on a RAMdisk, loaded from
floppy at boot time. The floppy isn't even mounted -- the way we
upgrade is to replace the floppy and press "reset".
We don't use a remote server for anything since, well -- routers are
the backbone of the network...
-- PGP: 2047/2A960705 BA 03 D3 2C 14 A8 A8 BD 1E DF FE 69 EE 35 BD 74 See http://www.zytor.com/~hpa/ for web page and full PGP public key I am Bahá'í -- ask me about it or see http://www.bahai.org/ "To love another person is to see the face of God." -- Les Misérables