nanog mailing list archives
Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy
From: Robert Boyle <robert () tellurian com>
Date: Thu, 02 Aug 2007 11:49:44 -0400
At 09:30 AM 8/2/2007, Craig D. Rice wrote:
For four months dozens of our users who are Comcast subscribers have had difficulty reaching St. Olaf College's and Carleton College's network services.We have worked through everything we can think of with our Onvoy (regional ISP) network engineers. We have isolated the problem a couple of Comcast's IP subnets, but need a contact within Comcast to further troubleshoot.
(snip)Either your firewall/router or the customer's firewall/router is blocking PMTUD packets. Fragment needed, but don't fragment bit set. Look at your ICMP access list and make sure you are allowing: permit icmp any any unreachable from any Internet address. I suspect an overzealous firewall admin is blocking all icmp. Read the acronym to him/her and explain that some icmp is necesary for the Internet to work.
-Robert Tellurian Networks - Global Hosting Solutions Since 1995 http://www.tellurian.com | 888-TELLURIAN | 973-300-9211 "Well done is better than well said." - Benjamin Franklin
Current thread:
- I35 bridge collapse in Minneapolis Sean Donelan (Aug 01)
- Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Craig D. Rice (Aug 02)
- RE: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Durand, Alain (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy William Herrin (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Robert Boyle (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Jim Shankland (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Adrian Chadd (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Jim Shankland (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Valdis . Kletnieks (Aug 02)
- Re: Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Duane Waddle (Aug 02)
- Seeking Comcast Contact: need to troubleshoot packet loss and/or asymmetric routing issue between Comcast & Onvoy Craig D. Rice (Aug 02)