[CentOS] Power-outage

Sat Jul 2 14:45:11 UTC 2011
Robert Heller <heller at deepsoft.com>

At Sat, 02 Jul 2011 14:52:27 +0200 CentOS mailing list <centos at centos.org> wrote:

> 
> Emmanuel Noobadmin 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.
> 
> > Like others have suggested, a cheap UPS is the way to go.
> 
> I'm convinced.
> Could you (or anyone) suggest a cheap UPS?
> This is only a tiny server (HP MicroServer) on a home LAN.
> 
> > The problem
> > with your idea is that you'll need a DC to AC inverter that can handle
> > the output current required by your server and something to hold the
> > batteries (you'll need more than one because attempting to draw a huge
> > current from a normal battery will either kill it or at the very least
> > cause it to have a shorter than expected capacity) and everything
> > together, it's probably going to cost more in both money and time to
> > have this thing.
> 
> I'm sure you are right, as I know nothing at all about power supplies.
> But surely computers actually use DC,
> so couldn't my torch-battery device just supply the PC components directly?

A PC uses several *different* DC voltages: +12, +5, +3.3, and several
others and they need to be *precise*.  Some of these are not an exact
multiples of the standard 1.5V Carbon-Zinc cells typicaly used in torch
batteries.

> 
> Many decades ago I went to lectures at university given by Fred Hoyle
> (famous at the time for a TV series where he said God was unnecessary).
> The lectures (on thermodynamics) were not really very good,
> but they were interesting because Fred Hoyle was slighly paranoid,
> and believed evil capitalists were foisting unnecessary devices on us.
> 
> One of his pet theories was that cars did not need huge accumulators,
> but could be started with a torch-battery.
> 
> Another was that incandescent bulbs were deliberately made to fail
> after a certain time.
> 
> Another was razor blades, which according to him could easily last for ever.
> 
> One interesting idea was that instead of nuclear power stations
> it would be cheaper, and give the same energy, to plant trees
> in a strip around the equator (I forget how wide).
> 
> 
> 
> 
> 
> 

-- 
Robert Heller             -- 978-544-6933 / heller at deepsoft.com
Deepwoods Software        -- http://www.deepsoft.com/
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