Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy

Thu Aug 2 14:09:38 UTC 2007

On 8/2/07, Craig D. Rice <cdr at stolaf.edu> wrote:
> We have already attempted the usual troubleshooting and have eliminated user
> problems, computer problems, server problems, cable modem problems, and
> Linksys router problems. Traceroutes have been somewhat inconclusive since
> Onvoy blocks ICMP within its network.

Craig,

This rings a bell. Do they block the mandatory ICMP
fragmentation-needed messages?

Try this: on your web server, reduce the MTU from 1500 bytes to 1400
bytes and see if the affected comcast users can now access your web
server.

Regards,
Bill Herrin

-- 
William D. Herrin                  herrin at dirtside.com  bill at herrin.us
3005 Crane Dr.                        Web: <http://bill.herrin.us/>
Falls Church, VA 22042-3004