Re: TASS UPS, Tech Note.

["John D. Gwinner" <gwinner@northnet.org>]

Herbert:

> A more "robust" reset would be to shutdown the PC's power supply
> via an AC disconnect. It would have the additional virtue of shutting
> down the AC supply - sometimes they "hang". I had suggested a
> mundane AC daily timer control that would shutdown the PC *every day*,
> an assured restart at a convenient time resolves a number of problems.
> Some may not like this solution, but it costs $10 and is fairly idiot
> proof, and it saves energy if you power down for a signifigant period.

I really don't like this suggestions, as the 10 dollar timer has no idea if
you've got files open at that time.  You are practically guaranteed to
loose open files at some point.  A watchdog timer, or periodic (software)
reset has the same problem of course, but with the advantage that the only
time the watchdog will reset is if the machine has hung, not when it's
humming along fine.  A software reset will gracefully close file handles,
tell applications there time is over, etc.

In the days of multi-tasking operating systems, I think it's very very
dangerous to just unilaterally power off a machine.  Powering off a UPS if
the UPS connects to the serial port to tell the PC to shut off would
probably work OK (assuming that UPS monitoring software is available and in
use, which isn't tough).

		== John ==