From: Gaurav Sabharwal
Sent: Tuesday, January 23, 2001 1:18 PM
To: datacenter@shorty.com
Subject: DATACENTER: Spacing issue?
Let's say I am placing 6 ft. x 2ft x 3 ft. racks in a room. The racks will
be in rows. What according to the experts is the optimum distance between
two rows?
Thanks and Regards,
- Gaurav
From: Martin Hannigan
To: datacenter@shorty.com
Subject: Re: DATACENTER: Spacing issue?
Date: Tue, 23 Jan 2001 15:05:11 -0400
At 10:18 PM 1/23/2001 +0400, you wrote:
>What according to the experts is the optimum distance between
>two rows?
I'd say 3'.
Hope that helps.
-M
From: Greg A. Woods
To: Gaurav Sabharwal
Cc: datacenter@shorty.com
Subject: Re: DATACENTER: Spacing issue?
Date: Wed, 24 Jan 2001 03:24:50 -0400
[ On Tuesday, January 23, 2001 at 22:18:10 (+0400), Gaurav Sabharwal wrote:
]
> Subject: DATACENTER: Spacing issue?
>
> Let's say I am placing 6 ft. x 2ft x 3 ft. racks in a room. The racks will
> be in rows. What according to the experts is the optimum distance between
> two rows?
Unlike other folks I've seen reply on the list so far, I no longer am at
all comfortable with just 4 feet of clearance between cabinet rows. I
want a full five feet these days, at least on the font side. This
doesn't mean you need to waste a lot more floor space though -- you can
probably get away with just three feet between the back-sides if you put
the rows back-to-back. This way you only "waste" two sq. ft. per
cabinet on the row(s) with front-sides facing out. In a small room you
can also often get away with butting one end of each row up against a
dead wall thus saving another 20 sq. ft. or so per row.
If your cabinets are 3 ft. deep then you have to consider that
eventually someone will be inserting and removing equipment that's
taxing the depth of those cabinet, i.e. up to 26-28 in. deep itself
(most "rack optimised" servers are very "deep"!). If such a chassis is
heavy and on sliders, you'll need to have it _on_the_rails_ while it is
sticking out of the cabinet by 2-6 inches, and another 2-10" to remove
it from those rails.
I.e. even 4 ft. of clearance is often not nearly enough room between
rows, especially if you end up in the position of having to be on the
opposite side of a big 150 lb. chassis fully extended on its rails.
Even if you can walk around the end of the ajacent row to achieve this
position it's sometimes highly sub-optimal to do so, especially if your
co-workers are currently supporting its full weight while they wait for
you to unstick a stuck rail or remove that last cable you forgot to
unplug! :-)
Sometimes even a relatively shallow chassis might need a full four feet
clearance just in order to mount it on its rails, eg. when the rails
stick out about 10" inches from the back of a 24" chassis and the
sliders in the cabinet are 10" out from the face when they are locked in
their extended position. That's at least 44" of clearance, and you're
now working at lining up heavy equipment to rails at just 4" from the
door of the opposing row of cabinets. These are, BTW, real measurements
from some of my own equipment and assosicated rails. I've even got an
18" deep IBM server that needs a full 3.5 feet of clearance to get it on
or off its vendor supplied sliders!
However if you end up with even deeper IBM/Dell/Compaq cabinets or
anything similar and the various new servers with 30-35" deep chassis,
you'll be needing a full five feet of clearance, if not more, on the
front side of the cabinets in order to get anything so deep in or out of
them, especially if it's more than 4u high (and thus very heavy!).
Sun's data center site planning guide has good information on how much
clearance different types of cabinets and chassis require, and how to
deal with air-flow issues at the same time:
--
Greg A. Woods
From: jlitvany@bbo.com
To: gaurav@antitopia.net, datacenter@shorty.com
Subject: RE: DATACENTER: Spacing issue?
Date: Tue, 23 Jan 2001 15:47:07 -0400
Gaurav,
If you are on raised floor, to minimize floor cuts, stick with 6ft. center
to center. This means you will have 3ft. between each row and you are able
to pull a full tile. It maximizes your space. For open architecture (telco
or universal) racks, go with at least 4ft. center to center.
-Jon Litvany