RE: Redundant Power

But if that large important piece of the mainframe communications
network had redundant power supplies on two separate circuits, it would
not have gone down.  There for they did not have full redundancy for
that application.


Christopher Bipes
Information Services Director
CrossCheck, Inc.

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-----Original Message-----
From: midrange-l-bounces@xxxxxxxxxxxx
[mailto:midrange-l-bounces@xxxxxxxxxxxx] On Behalf Of Larry Bolhuis
Sent: Tuesday, May 30, 2006 11:16 AM
To: Midrange Systems Technical Discussion
Subject: Re: Redundant Power

Rob,

Like anything else with redundancy, it's just a question of how far 
you can afford to take it.  Unless you can provide it on all sorts of 
levels (2 UPSs, 2 independant power feeds, 2 power companies with 
independant supplies, etc.) there's always a point of failure 
somewhere that will bite you!
  

And it happens My old neighbor worked in just such a data center. Dual
feeds, dual generators, dual UPS, then into a magic box that split the
load. And one thing per circuit. One. Even if it was a modem if it
tripped it's breaker, nothing else died.

Then one day they were searching for an open circuit on which to place a
new outlet. They thought they had found an existing one that wasn't in
use So they shut off the breaker and then tested it. It sill had power. 
Hmm, then what Doesn't have power? Some large important piece of the
mainframe communications network, that's what. Only took them a day to
recover!

We humans can find a way to screw up ANY unbreakable solution.

  - Larry

             rob@xxxxxxxxx