[119025] in North American Network Operators' Group
Re: HE.net, Fremont-2 outage?
daemon@ATHENA.MIT.EDU (Owen DeLong)
Wed Nov 4 17:22:54 2009
From: Owen DeLong <owen@delong.com>
In-Reply-To: <db57f93c0911041408j5f5bb4aag44375585e5161d4f@mail.gmail.com>
Date: Wed, 4 Nov 2009 14:18:04 -0800
To: Raphael Carrier <raphael.carrier@gmail.com>
Cc: "nanog@nanog.org" <nanog@nanog.org>, Joe Greco <jgreco@ns.sol.net>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Nov 4, 2009, at 2:08 PM, Raphael Carrier wrote:
>> I know you have a rather higher faith in batteries than some of us,
>> but practical experience suggests that batteries are merely a mostly-
>> reliable technology.
>>
>
> Agreed batteries are unreliable, an alternative to battery based UPS
> are flywheel energy storage devices, they come either as an integrated
> solution with the diesel generator (i think cat offers such a package)
> or as a standalone UPS (see:
> www.pentadyne.com/uploads/18/File/Pentadyne-VSS-Brochure.pdf)
>
Apparently you do not remember 365 Main...
Batteries are reliable.
Flywheels are reliable.
Both require proper maintenance and proper procedures to handle
corner cases (like the multiple-outage corner-case that took out
365 main).
Both have their issues.
In my experience working at and with a variety of datacenters, I have
to day that I have had generally better luck with batteries than
flywheels,
but, the key difference that suggests flywheels could actually be better
technology is this:
About 50% of battery failures traced back to human factors.
100% of the flywheel failures I experienced were human factors related.
Owen
Speaking as an individual, not representing any affiliation.
