[151742] in North American Network Operators' Group
Re: Comcast Ethernet Feed
daemon@ATHENA.MIT.EDU (Derek Ivey)
Thu Mar 29 20:57:26 2012
From: Derek Ivey <derek@derekivey.com>
In-Reply-To: <4F75028F.9070109@2mbit.com>
Date: Thu, 29 Mar 2012 20:56:57 -0400
To: Brielle Bruns <bruns@2mbit.com>
Cc: nanog@nanog.org
Errors-To: nanog-bounces+nanog.discuss=bloom-picayune.mit.edu@nanog.org
This.
We have a Comcast MetroE PtP connection between our office and our =
datacenter and I found that it was defaulting to half duplex. I forced =
both of my ends to 100 Full and it fixed my issue.
Derek
On Mar 29, 2012, at 8:47 PM, Brielle Bruns wrote:
> On 3/29/12 6:36 PM, Brian R. Watters wrote:
>> We are about to accept a 20MEG Ethernet feed via Comcast and their
>> fiber plant as well as a BGP feed across the same link.
>>=20
>> I have a space GIGE interface on a 7206VXR and would like to know
>> best practice for deploying for optimal performance across this
>> interface.
>>=20
>> Any ideas and or direction would be extremely helpful as we are
>> seeing some real issues such as.
>>=20
>> Direct connect (without BGP) to the CPE from Comcast (Fiber to
>> Ethernet) via a laptop gives the level of performance we would
>> expect, However as soon as we terminate to our router via the GIGE
>> which is set to 100MB full duplex and all flow control turned off
>> (Negotiation auto) per Comcast and connect up via a 100MB fast
>> Ethernet interface directly connected we get a fraction of the speed
>> when direct connected.
>=20
>=20
>=20
> =46rom my own experience here with our 7200s, some of the PA based =
100BaseT interfaces (ie: not on the IO module) can not negotiate =
100-full, but rather only half. This leaves one end diff then the other =
and creates issues with performance. Try forcing both the laptop and =
router to 100-full and see if it helps.
>=20
>=20
> --=20
> Brielle Bruns
> The Summit Open Source Development Group
> http://www.sosdg.org / http://www.ahbl.org
>=20
