Very Computer

I want to get a UPS for several Linux systems.  I need to be able to use
signaling so that the machines will cleanly shut down in the event of a
power outing.  I will use apcupsd to do this.

I'm looking at both the BackUPS (USB versions-- the RS and the Pro) and
the SmartUPS from APC.  The SmartUPS seems to cost a factor of two more
than the BackUPS (for a given power rating), but from apcupsd I can't
tell what the difference is.

*Is* there any practical difference between the BackUPS and SmartUPS if
you're using apcupsd?  If so, what is it?

Thanks,

-Rob

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The SmartUPS models were more intelligent.  They would report things like
the input line voltage and temperature.  Plus you could signal the UPS to
shut off, do self-tests, and other things.  I'm using one of the older
serial SmartUPS models here at home and I really like it.

If you want to save some dough, find someone tossing out their UPSes and
snatch them up.  It seems that everyone forgets that lead-acid batteries
only last a few years.  So when the batteries go, they toss the whole UPS,
thinking its broken.  Grab the bad UPS, find yourself a battery store or a
burgler alarm supply store and replace the batteries.  Then, be a good
citizen and drop off the bad batteries at your city/county local recycling
drop-off so they don't end up in the landfills.
I got a small BackUPS 520 a few years ago that way; replacement batteries
cost me all of $22 at a hamfest.

good luck...

But the main difference is the manageability and upgradability of the
SmartUPS line.  They have a "Smart Slot" for optional items such as
network (SNMP) management (instead of serial/USB), environmental
monitoring, and so on.  

IOW, with the SmartUPS line you have the option of upgrading to add
features which are important for use in a data centre whereas the
BackUPS line is targeted more at office use.

One advantage of the SpartUPS is the ability to handle a broad range of
loads - for instance APC has an app note about using one for inductive
loads (motors, such as a sump pump).  Most UPSs will burn out with an
inductive load.

PS: I recommend hitting the APCUPSD website (www.apcupsd.com).  Not only
does the driver work well for me, but it has lots of useful information
(such as which UPSs advertised as simple-signalling really support a
subset of smart, which UPSs claim to be USB only but really also support
serial, schematics for most of the weird cables APC uses, etc.).

                Ken Ryan