[Beowulf] Emergency Power Off

Robert G. Brown rgb at phy.duke.edu
Sun Mar 18 06:52:25 PDT 2007

To answer my own question (GIYF, after all:-) there is a white paper


that does indeed address this very question.  The answer (in a nutshell)
is that an EPO is required by code to protect a "data center".  A
datacenter has a very specific definition, and just not having fire
resistant walls suffices to make something "not a data center" and hence
exempt.  This is bizarre and backwards, of course.

Hence most wiring closets and small server rooms, including the
one I'm working on, appear to be exempt.  There are also significant
requirements on room air conditioning for data centers under the same
code, BTW -- the HVAC has to also be disconnectable, and the air returns
have to be

HOWEVER, if you love your local firemen and want them to live (or love
yourselves and the other employees who sit near the data not-a-centers),
the same white paper says that an EPO switch is still a very good idea
for small server rooms and wiring closets that are not "data centers"
but are just "data closets" or "data rooms that aren't quite centers".

This white paper STILL doesn't help a whole lot with the actual nuts and
bolts of how to wire a room kill -- it makes is seem like every room is
supposed to be a unique piece of engineering where you should expect to
drop thousands of dollars on the process (more than the cost of the
UPS's being controlled by a factor of two or so) rather than a simple
"wire the following standard cat5 rj45 cables from here to here, plug
them into the EPO switch suitably mounted on the wall here, test" type

But I will persevere.  Google is still there, and the information I seek
MUST be somewhere in webland...;-)


Robert G. Brown	                       http://www.phy.duke.edu/~rgb/
Duke University Dept. of Physics, Box 90305
Durham, N.C. 27708-0305
Phone: 1-919-660-2567  Fax: 919-660-2525     email:rgb at phy.duke.edu

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