Back-UPS garbage? (was: Quick survey -- UPSs on slave nodes?)
drew-list-beowulf at poured.net
Tue Feb 11 07:57:25 PST 2003
"Robert G. Brown" <rgb at phy.duke.edu> writes:
> On Mon, 10 Feb 2003, Drew Raines wrote:
>> Has any one of you actually used these to sustain a PC for any
>> measurable length of time? I'm not sure at what market this
>> junk is aimed, perhaps suckers.
> In the Durham NC residential grid we have a power outage that
> lasts approximately one second approximately once a month.
> I've recently started putting my home computers (which are all
> members of my home cluster:-) on $50 cheap UPS because they are
> enough to sustain a system across these frequent, short, outages.
I work in a university research building where you'd expect the
power to be consistent, especially since the whole medical center
is battery-backup'ed (critical hospital systems being the primary
Oddly enough, we see those spikes or flickers all the time, so I
got a Back-UPS 350 with the hopes of doing exactly what you said,
surviving the frequent, short, outage. No go.
After trying two machines and a monitor on the battery-backed
plugs, just the two machines, and finally just one machine, I got
the stupid thing to provide a couple seconds of life. But that was
it. The box said 17 minutes under average load. I'd think one
200-watt power supply would be average enough.
That was my Dell Precision 530 PC, sans monitor. When I tried only
my Sun Ultra 30 (again, no monitor), *beep*, reboot.
And then APC has the audactiy to include a serial cable as if
that's useful. Until I find the serial port on my clock radio,
that does me no good. (I've seen reports from others, though, that
only the Smart-UPS line and up can signal a machine to safely
Long story short, I replaced it with a Smart-UPS 650 which seems to
support both systems through mild outages. For $275, though, I
wanted it to log in, check my e-mail, and respond appropriately to
outstanding messages before it signaled a machine to halt. Oh
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