At Fri, 01 Jul 2011 17:36:56 +0100 CentOS mailing list <centos at centos.org> wrote: > > Rudi Ahlers wrote: > > >> It seems to me that it should be possible > >> to have a simple, torch-battery operated, system > >> which will keep the machine alive long enough > >> to make a graceful exit. > > > A UPS would be your simplest option here since the UPS can send a > > signal to the OS to shutdown properly. > > > > Using a "torch battery" (I presume this is a large torch?) you'll > > still have the same issue as you have now - when the battery runs flat > > (i.e. power outage is longer than 10 minutes or so) Linux will still > > crash uncleanly. > > As will be obvious, I know nothing in this area. > My thought was just that the machine only requires say 30 seconds of life > to shutdown properly, and I would have thought > there was enough capacity in a large torch battery to supply this? What do you mean by 'torch battery'? If you mean the D cells typical of a flashlight (flashlight is 'American' English for [electric] torch), no this is not going to power a computer for more than fraction of a second. If you mean a 'lattern battery' (a larger 6V battery, used in typical upright camping latterns), maybe, but you are going to need an inverter, etc. to feed AC to your computer's power supply. > > But there seems to be a 100% backing for UPS, > so I'll look into that. Yes. They are not terribly expensive, partitularly if you are not looking for a large one or a 'fancy' (excessive 'bells and whistles') one. For a small server, a typical consumer-grade UPS costing like US$100 will do everything you need. These little consumer-grade UPSes, basically consist of a rechargable 'lattern battery' sized rechargable battery (commonly a gel-cell lead-acid type battery), a charger for the battery, and an inverter to re-create the AC power for your equipment (computer). All in one box. Most now have some simple 'smart' electronics with a simple micro-processor element with a USB connection that will talk to your computer telling it how things are going (on Mains, on battery, battery charging, battery charged, battery discharged, current load levels, Mains voltage, etc.). > -- Robert Heller -- 978-544-6933 / heller at deepsoft.com Deepwoods Software -- http://www.deepsoft.com/ () ascii ribbon campaign -- against html e-mail /\ www.asciiribbon.org -- against proprietary attachments