At Fri, 01 Jul 2011 17:36:56 +0100 CentOS mailing list centos@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.).