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David Kewley wrote:
<blockquote cite="mid200601090316.13861.kewley@gps.caltech.edu"
type="cite">
<pre wrap="">On Sunday 08 January 2006 14:03, Robert G. Brown wrote:
</pre>
<blockquote type="cite">
<pre wrap="">I've never heard anyone say they were particularly happy having to mess
with cabling running under a raised floor (but have heard plenty of
griping) but there may be ways of laying it out nowadays that are easy
(easier) to manage.
</pre>
</blockquote>
<pre wrap=""><!---->
We have:
* AC units & their air intake directly behind racks
* ceiling-ductwork cooling to front of racks
* under-raised-floor cooling to front of racks
* under-floor routing of chilled water, power, and a few random things
* overhead cable-tray routing of network (a very open tray, easy to use)
Power comes in the bottom-rear of the racks, and network comes in the
top-rear. We have nearly no top-bottom homogeneity of ambient temperature
in the racks, due to the up-down airflow and the large area in the front of
the racks that allows much mixing. I say "nearly no" because the top 2-3
1U machines *are* a few degrees C warmer, likely because of recirculated
hot air *inside* the racks.
</pre>
</blockquote>
With our dell racks we have the same issue where the top 1U server runs
3-4 degrees hotter then the 2nd below that the difference 1-2 degrees
for the 3rd and then it is more or less the same for the other nodes. I
think it is caused by the front pannel of the dell racks not being
perforated all the way to the top, which blocks the airflow comming
from our AC.<br>
<br>
Temps are well within operating limits though so I don't worry about it
too much.<br>
<br>
<pre class="moz-signature" cols="72">--
Ben Vanhaeren
System Administrator
RF&M SCK-CEN
Tel: 014 33 22 16
Mob: 0498 54 59 05
</pre>
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