[NTLUG:Discuss] UPSs

[Kelledin]

On Friday 13 June 2003 09:51 am, JM5379 at sbcglobal.net wrote:
> I'm looking for recommendations to present to management for
> reliable and relatively inexpensive UPSs for a single Linux
> server.

APC.  I've had excellent results with all APC products.

There are a few gotchas to consider about UPS units that don't 
always show up on the label.  One is standard battery life (how 
long do the factory-installed batteries last), and another is 
what replacement battery packs it needs (RBC 6/8/9/12/whatever).  
Also keep an eye out for leak-proof batteries when shopping for 
spare batteries; leaky UPS batteries can be a serious problem, 
perhaps even damaging the UPS itself.

APC UPS's generally come with leak-proof, high-quality batteries 
that last upwards of five years.  Their battery use is also very 
efficient; for example, an APC 1000VA UPS takes smaller, less 
expensive battery packs than a Tripp-Lite OmniSmart 850VA unit.  
I know this from experience, because the 850VA Tripp-Lite unit 
under my desk has dead batteries, and I can't afford to replace 
them at the moment.  Also, the Tripp-Lite factory-installed 
batteries barely lasted three years.

I'm now wishing I'd bought an APC unit. :(

Remote management options are also a big plus, especially if 
you're putting more than one system on a single UPS.  For a 
single workstation with a dedicated UPS, a simple 
contact-closure signal over a serial cable are "good enough," 
but not necessarily for three or so servers.  Generally, the 
more systems you have hanging off a UPS, the more management 
features you want.

Also, one BIG gotcha--you can safely have a UPS hanging off a 
surge suppressor, but you should _not_ have a surge suppressor 
hanging off a UPS.  I'm not quite clear as to why, but my 
understanding is that you lose some of your protection features 
because of the way the suppressor and UPS interact.  I'm also 
not sure it's good to daisy-chain one UPS to another.

-- 
Kelledin
"If a server crashes in a server farm and no one pings it, does 
it still cost four figures to fix?"