Skip site navigation (1)Skip section navigation (2)
Date:      Wed, 16 Oct 2013 19:37:26 +0200
From:      Johan Hendriks <>
To:        Frank Leonhardt <>
Cc:        freebsd-questions <>
Subject:   Re: UPS buying suggestion
Message-ID:  <>
In-Reply-To: <>
References:  <> <>

Next in thread | Previous in thread | Raw E-Mail | Index | Archive | Help
Op dinsdag 15 oktober 2013 schreef Frank Leonhardt (

> On 15/10/2013 06:07, yudi v wrote:
>> I am planning on buying an UPS to protect my HP microserver
>> n40l<**wiki/HP_MicroServer_N40L_Wiki<>;
>> >**,
>> it will be running FreeBSD 9.2 RELEASE.
>> I am looking at
>> APC Power-Saving Back-UPS ES 8 Outlet 700VA 230V AS
>> 3112<**products/resource/include/**
>> techspec_index.cfm?base_sku=**BE700G%2DAZ&total_watts=400<>;
>> >
>> is that supported by apcupsd? (already tried apcupsd mailing list, there
>> was no response, hence asking here)
>>   If not, please recommend one that is supported.
>> The HP server has a 150W PSU and the UPS is rated at 400Watts, and it
>> comes
>> with USB monitoring support.
>> Also, how to measure exact power consumption by a device?
> I've been watching this thread with a bit of interest. For what it's worth
> I run several UPS units at various location (about forty) and FWIW I tend
> to avoid the cheap ones although I've not actually had a problem with them.
> It's just when I open the case I don't like the manufacturing quality. I'm
> using (right here) an APC BackUPS Pro 420 to keep three HP microservers
> alive. What!? Yes, it works. The power they draw varies greatly depending
> on what type and how many drives you have in the bays and (I think with the
> Microservers) their processing workload.
> As to the "compatibility", I do the myself. All I want it to do is shut
> down gracefully if the power fails - nothing more. And this is how I do it:
> All servers are, by definition, connected to the network. They can ping
> equipment nearby (just do it from a shell script). If they ping several
> pieces of kit on the LAN that don't have a UPS and get no reply, repeatedly
> for a few minutes) then it can be assumed something's up, and they can shut
> down. As a cross-check they can ping other kit on a UPS and if that's still
> alive it proves the NIC is okay. In the event of a suspected failure the
> script writes what it's done in a log, emails it to me (for later) and
> calls shutdown.
> Why don't I use a special driver? First off, one UPS may be powering more
> than one server but only one can be connected (and I've got a few *BIG* UPS
> units covering a whole rack). Secondly, UPS units need servicing, which
> means they get swapped. Unless you have just one type you've got more than
> one protocol to contend with, and is that USB or RS-232? It quickly becomes
> a pain. I want to be able to swap any UPS for any other and still have
> automatic shutdown without messing with the server hardware/software.
> So, what I look for in a UPS is a good automatic self-test (i.e. a "smart"
> one) and a standard and easy to change battery (the 7Ah type are cheap,
> plentiful and are thus well refined).
> As to the "run time", there are lies, damn lies ans statistics. I once
> tested a load of them for an article in PC Magazine and took very little
> notice of what the manufacturer said. They normally have the same battery,
> and without breaking any laws of physics they're going to run for pretty
> much the same time unless they're using a cheap and inefficient inverter,
> in which case the energy gets dissipated as heat and you'll know it.
> Inverters are a done deal now - just buy the chip - I wouldn't expect much
> variation. The only performance difference you're likely to find is the
> output current, and the transistor it flows throug - if it's weedy it will
> overheat/burn out, but that takes time. You pay more for sustained higher
> output currents, but may very well not need them. As to the run-time,
> that's always down to the battery capacity. Buy a new one every two years;
> don't wait for the load test to fail.
> Regards, Frank.
> ______________________________**_________________
> mailing list
> To unsubscribe, send any mail to "

Hello Frank,
I like the idea of the power canary so to call it.
Would you mind and share the script?


Want to link to this message? Use this URL: <>