HE.net, Fremont-2 outage?

Joe Greco jgreco at ns.sol.net
Wed Nov 4 01:23:48 CST 2009


> Regardless of generator sizing issues or disparities, if the ATS fails, 
> then no amount of grid or generator power will keep the cabinets juiced up.

Sure.  Having no direct knowledge of the HE DC in question, I was merely
commenting on the issue I replied to.

> Since this is the second time in recent history that this building has 
> experienced a short power outage caused by ATS flakiness, 

Has this been verified?

> perhaps 
> keeping a small UPS in the cabinet isn't such a bad idea? Even if the 
> distribution switches/routers lose power, at least the servers wouldn't 
> have to go through fscks and DB integrity checks due to unplanned power 
> loss, and the recovery time would be significantly faster.

Small UPS's have their own set of ugly failure modes.  For example, we
find that the APC Smart-UPS 1400's have a tendency to cook their
batteries; if you don't have monitoring of some sort, you may not find
out that your batteries are cooked until the UPS decides it is hopeless
and shuts itself off.  In the meantime, the lingering sulfur smell may
panic someone...  or cause a falsing of the fire system...

Colos frequently forbid the use of small UPS's for a variety of reasons.

> Hell, for a 5 minute power outage, some of my services were down for 20 
> minutes. I'll happily take a 75% reduction in downtime for the cost of a UPS
> , though clearly redundancy across more reliable datacenters is a better 
> solution.

So is redundancy across power systems within the colo, but only for well-
designed colos.  Stories omitted.

... JG
-- 
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.




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