[CentOS] Emergency rescue help needed

[Les Mikesell]

Sorin Srbu wrote:

> 
> The voltage has been fairly constant here over the years since I started using
> UPS and logging the voltage and stuff, 238V more or less constantly. It rarely
> drops below 236V or over 240V. We mainly use the UPS:es to have controlled
> shutdowns should the power fail entirely - We had some issues a few years back
> while they built a new school the other side of the road when the power went
> up and down for a uyear or so, and the diesel-generators didn't start up as
> expected. This whole building where I work is supposed to be a wartime
> hospital with power-backups up to yinyang. But it failed when we needed
> them... #=;-(

It's a tough thing to get right.  I've been involved with several 
systems and they all failed a time or two in initial testing even after 
everyone thought they should work.  And then things break after that...
> 
> It might be that the power is too high, although the standard is 240V in
> Europe AFAIK. Or the UPS-units *may* have been rated for the previous lower
> voltage-level at 220V, but that sounds a bit farfetched IMO. Unless the units
> were a (very much) older batch that APC dumped on us...

Another issue can be that you aren't backing up the air conditioner 
power, so when the grid goes down your still-running equipment 
overheats, damaging the electronics.  This is particularly likely if 
your servers are racked densely in a small space.

-- 
   Les Mikesell
    lesmikesell at gmail.com