[130055] in North American Network Operators' Group
Re: Routers in Data Centers
daemon@ATHENA.MIT.EDU (Christian Martin)
Sun Sep 26 22:47:42 2010
In-Reply-To: <20100927022907.GW1946@gerbil.cluepon.net>
From: Christian Martin <christian.martin@teliris.com>
Date: Sun, 26 Sep 2010 22:46:48 -0400
To: Richard A Steenbergen <ras@e-gerbil.net>
Cc: Alex Rubenstein <alex@corp.nac.net>, "nanog@nanog.org" <nanog@nanog.org>
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
On Sep 26, 2010, at 10:29 PM, Richard A Steenbergen <ras@e-gerbil.net> wrote=
:
> On Sun, Sep 26, 2010 at 09:24:54PM -0400, Alex Rubenstein wrote:
>>=20
>> And, not to mention that some vendors do it sometimes.
>>=20
>> "The 9-slot Cisco Catalyst 6509 Enhanced Vertical Switch (6509-V-E)=20
>> provides [stuff]. It also provides front-to-back airflow that is=20
>> optimized for hot and cold aisle designs in colocated data center and=20
>> service provider deployments and is compliant with Network Equipment=20
>> Building Standards (NEBS) deployments."
>=20
> A classic 6509 is under 15U, a 6509-V-E is 21U. Anyone can do front to=20
> back airflow if they're willing to bloat the size of the chassis (in=20
> this case by 40%) to do all the fans and baffling, but then you'd have=20
> people whining about the size of the box. :)
I would point out that it is quite possible to build a compact (say 4-5 U) f=
ront-back airflow platform if vendors were willing to pay to engineer a smal=
l midplane and leverage modular I/O cards in a single vertical arrangement. =
As an example, envisage an M10i with 8 single height PIC slots, rear mounte=
d RE/PFE combos, and a top/bottom impeller. Same for a 72/73xx, or whatever=
platform you fancy. But would it make business sense? You'd lose rack spa=
ce in favor of thermal efficiency. =20
I think the push toward cloud computing and the re-emergence of big datacent=
ers with far more stringent power and heat restrictions may actually drive s=
uch a move. I guess we'll see...
C
>=20
>> It only took 298 years from the inception of the 6509 to get a=20
>> front-to-back version. If you can do it with that oversized thing, it=20
>> certainly can be done on a 7200, XMR, juniper whatever, or whatever=20
>> else you fancy.
>=20
> Well, a lot of people who buy 7200s, baby XMRs, etc, are doing it for=20
> the size. Lord knows I certainly bought enough 7606s instead of 6509s=20
> over the years for that very reason. I'm sure the vendors prefer to=20
> optimize the size footprint on the smaller boxes, and only do front to=20
> back airflow on the boxes with large thermal loads (like all the modern=20=
> 16+ slot chassis that are rapidly approaching 800W/card). Also, remember=20=
> the 6509 has been around since its 9 slots were lucky to see 100W/card,=20=
> which is a far cry from a box loaded with 6716s at 400W/card or other=20
> power hungry configs.
>=20
> Remember the original XMR 32 chassis, which had side to side airflow?=20
> They quickly disappeared that sucker and replaced it with the much=20
> larger version they have today, I can only imagine how bad that was. :)
>=20
> --=20
> Richard A Steenbergen <ras@e-gerbil.net> http://www.e-gerbil.net/ras=
> GPG Key ID: 0xF8B12CBC (7535 7F59 8204 ED1F CC1C 53AF 4C41 5ECA F8B1 2CBC)=
>=20
