David Rankin <[EMAIL PROTECTED]> wrote:
> Sorry if this is a little off topic:
>
> I had my LM7.2 server go down for the 4th time due to a power
> outage. I had to manually fsck /dev/hda7 to bring the system back up. I
> am convinced that this is not a good way to treat the server and I am
> going to buy an APC UPS to keep it from happening again.
First, go get nut, and join the NUT mailing list.
Second, DO NOT BUY APC! ESPECIALLY DO NOT BUY a BackUps! But I'd
say just avoid them. (Sorry for yelling, but their supposedly
RS232-C 'signaling' scheme is not RS232 compliant, and if your
serial port requires valid RS232 signal levels you wont' be able
to detect low battery (as it only goes to zero VOLTS - some (most?)
pc hardware is really sloppy and will take a zero volt as a valid
level, but that's not according to spec - and some hardware (like,
say, Sun) actually meets spec and will NOT see LB from the UPS
without a fair amount of hassle. why do I say all this, and
where do I get my knowledge? I'm trying to get 4 stupid APC
BackUPS' to work with our Sun Ultra5s - and if there was any
way I could SEND THE RETARDED THINGS back and get something
else I would do it in a nanosecond!)
Um, lets see, where was I? Sorry...
Oh - yeah. Starting again:
Go buy something besides an APC (or get a SmartUPS). Get and
install NUT (look on freshmeat or sourceforge, and if you cannot
find it there email me and I'll go look up the correct url),
install it, configure it for your UPS and for the shutdown mode
you want, test it by pulling the plug. And you're done.
> What I need to know is if anyone has any advice on how to configure
> the APC box to send a shutdown signal over the serial port to nicely
> shut the server down. I don't have any experience with UPS's and just
> want to make sure I'll be able to accomplish getting the UPS to talk to
> my server and shut it down before I go spend the money on a UPS.
The APC BackUPS are mostly worthless, in my mind. Most of the really
cheap ones are, really, as they use the 'simple signalling' method
which means you get the following signals: on battery (or on AC mains),
low battery (if you're lucky); and your control signal is "shut down".
The better way to go is to get a 'smart' ups (again, I stronly advise
against APC, but if you get the APC SmartUPS at LEAST it usually works
with serial ports), which can give you all kinds of cool info, like
loading, battery health (I think), temperature, and stuff like that.
They also (as I said) use rs232 to transmit DATA (ascii, usually,
but not always) about themselves (and usually accept commands that
way also, including shutdown). Definately worth the price if you
want your machine to be able to shut down well AND keep track of
the health of the UPS.
> All of the APC UPSs come with software to shut windows down, but
> don't say a thing about Linux. How do I get it to work with my server?
> Advise would be great, but if you can just point me to the right docs, I
> don't have a problem reading.
Again, look for UPS (or simply NUT) on freshmeat, they've got lots of good
info. (Warning - a google search will turn up LOTS of info - some of it will
say you can get a backUPS to give you LB signal - which turns out depends
upon your monitoring computer!).
And, finally, a word about NUT - you can do some really amazing stuff with
NUT, like have more than one ups powering something, have more than one
computer powered by the same ups and shutdown when the shutdown time
(usually low battery) comes around, stuff like that.
(Sorry to flame APC so much, but I've got 4 mostly useless APC UPS's
here that I'm really frustrated with...)
rc
Rusty Carruth Email: [EMAIL PROTECTED] or [EMAIL PROTECTED]
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