Re: [cobalt-users] 99.9% up time

[Jeff Lasman <jblists@xxxxxxxxxxxxx>]

Okay, you force me to explain myself...

Kris Dahl wrote:

> IMHO three nines is easy.  I could do that with crappy hardware and NT if I
> was careful.  I don't think I have a single machine (even a workstation)
> that isn't 99.9% available.

It's got nothing to do with any single machine or even "normal
conditions".  It's got to do with what happens after your power's been
down ten minutes and the battery's beginning to fail, and you don't have
a generator.  Or you do, but it hasn't been run in three years and you
have no idea if it'll start up or not until it doesn't.

Or, presuming you're multi-homed, but the backhoe that does the damage
is right outside your building and cuts all the wires.

Or you're really securely multi-homed, with three separate paths out of
your building, AND a dish on the roof.  And battery backup, and your own
diesel power, well tested, running properly, and everything else, and
one of your upstreams has a misconfigured router and your BGP just
happens to not work properly.  And it happens the weekend you're
vacationing in Hawaii and your BGP tech's cell-phone's battery is dead.

Attaining 99.9 isn't hard under normal conditions is easy.  Being able
to guarantee it under abnormal conditions is a bit harder.

Unless of course you want to become known (as are many tier one
providers) as having guarantees with no value.

> But if you want to guarantee 99.9%, you should invest in adequate power
> protection, and keep near-line backups if at all possible.  Also co-locating
> with a datacenter that provides the power and redundant connections with
> full BGP routing to multiple carriers would be the easiest way to do it.

I've got all of that, and charge accordingly.  I still don't guarantee
anything except best efforts.  (I guess that's what I mean by
"nobaloney".)

Jeff
-- 
Jeff Lasman <jblists@xxxxxxxxxxxxx>
nobaloney.net
P. O. Box 52672
Riverside, CA  92517
voice: (909) 787-8589  *  fax: (909) 782-0205