OT: Server Cabinet

Joe Greco jgreco at ns.sol.net
Thu May 5 13:50:25 CDT 2011


> > > If you have a need for a 4-post rack, do not accomplish that by
> > > using 2 2-po=
> > > st racks. You will likely find that rack rails that are designed
> > > for a 4-pos=
> > > t rack will not fit.
> > 
> > Why?  With *any* rack, there are always scenarios where the rack
> > rails for
> > some random item don't end up fitting right.  That's certainly not a
> > problem
> > inherent to two 2-post racks.  You can find 2-post racks in any
> > number of
> > interesting and unusual post/flange configurations.  It's certainly
> > true
> > that picking any old random 2-post rack has certain hazards
> > associated with
> > it - the solution is don't pick "any old random" one, not "don't pick
> > a
> > 2-post rack."  But the look-before-buying rule applies to any rack
> > you buy,
> > doesn't it?
> 
> The major issue is that 2-post rack rails are generally U-shaped,
> and have tapped holes.

Which some of us prefer, unless we're mounting lots of servers or
something like that.  When you're working with various odd bits of
networking gear, square holes just mean you get to do lots of cage
nuts until your eyes go crossed and you finally realize when putting
in that eighth screw on a big bit of equipment that you misaligned
the last cage nut.  And you know it's always the last one, and you
can't slide it because it's too tight.

> Server rack rails are L-shaped and generally have square holes.

Many are, yes.

> The vast majority of mounting rails I have seen in server 
> equipment, in the last few years especially, will not fit because
> of the extra inside rails. Been there, done that, had to buy a
> real 4-post rack.

I guess that could be.  My own experience in the last few years is
that it hasn't been a problem.  An old Cisco AccessPath rack I use
here in the shop for testing took several HP DLnnn servers with the
HP rails no problem; it's a tapped-hole beast but the HP rails just
needed the pegs removed and they worked fine, no worries about any
hangouts on the sides or anything else that I can recall.

> Is it really a big deal to spend $500 for the proper rack?

I believe we were making suggestions as to what the "proper rack"
might be, and that we haven't really heard any guidance as to what
the rack will be used for, so this is all speculation.

Myself, I kind of took a wild stab at "HP servers" because normally
one doesn't buy an HP rack for Dell servers.  Of course, there are
almost certainly HP servers with rails that won't work well in a
pair of relay racks.  I also didn't bother to duplicate suggestions
that others had already made; my listing of a single suggestion 
wasn't meant to imply that mine was the best recommendation or 
anything like that.

Speaking as someone who's had POP's in very small closet-like rooms,
I feel compelled to note that tales of various options, including
the good and the bad, would have been welcome many years ago.  Alas,
NANOG didn't exist back then.  As it stands, I don't think that one
can reach a conclusion as to what the "proper rack" for this guy is,
but I can say that from my own experience, folks have provided a 
very comprehensive set of options and a wealth of practical 
experience that ought to move things in the right direction.  It's 
been enjoyable to read, too...  you realize that many others have 
had some of those same cursing, swearing bad days out on the floor.

... JG
-- 
Joe Greco - sol.net Network Services - Milwaukee, WI - http://www.sol.net
"We call it the 'one bite at the apple' rule. Give me one chance [and] then I
won't contact you again." - Direct Marketing Ass'n position on e-mail spam(CNN)
With 24 million small businesses in the US alone, that's way too many apples.




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