On Sat, 2006-09-16 at 11:17 +1000, Andrew Lowe wrote: > > Just a slight hijacking of this topic, > I have a little EPIA server acting as firewall, npt, dhcp, dns,etc,etc. > Now even though it doesn't pull a lot of power, I don't want it running > all the time, it has something to do with missing ice caps. So I want to > build a button that attaches to the machine via, say, usb that when > pushed shuts the machine down. By a button I mean that sort of emergency > shutdown button that is usually red and used in industrial control, the > sort of thing the hero always has to push to save the heroine/world.
don't know about the James Bond stuff - you'd probably also need an lcd countdown where the button only works if you press it on 007... anyway, you probably don't want to go exactly the way of the industrial Emergency Stop, as it's a hardware cutoff - ie. power is shut of straight away, without any software intervention. Your disks will probably survive the unclean unmounts, and you power supply may handle the voltage / frequency spikes from the switch opening, but why bother? If you really want, you can pick them up from any electrical distributer (in Australia anyway)... > Does anyone here have enough hardware design knowledge to say if this > would be easy or not and as to whether I should just lower my sights and > stick to the three finger salute or the "normal" on/off switch? If I were you, I'd want to stay with the ACPI power button, most popular OS's can detect this nicely. What you can do is this: - "splice" the power switch cable (the motherboard/case one, NOT the power supply side!). The button works by completing a circuit to the motherboard when pressed, so you can have two buttons doing the same thing on the same circuit. Join a new wire of each of the two existing wires. (Inside your case, they're usually labelled PWRSW or something). - buy any sort of big red button (normally open, non latching) and wire it to the two new wires. I have a nice arcade "fire" button which would do the trick. - stick it on the top / front of your case with a sign saying "PRESS ME" (or maybe "don't touch" if you want to go for the reverse psychology angle...) voila! > p.s. The main reason driving this is that the wife never turns the > server off. If I have a Big Red Switch, I can say "But it has a big red > switch, how can you miss it????" you could try some "reNedufication", or perhaps a script that detects how many users are logged in and for how long, and then shutdown automatically. Or just shutdown at midnight (or whatever time she's guaranteed not to be on... -- Iain Buchanan <iaindb at netspace dot net dot au> fortune: cannot execute. Out of cookies. -- gentoo-user@gentoo.org mailing list
