to troubleshoot packet
loss and/or asymmetric routing issue between Comcast Onvoy
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
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
On 8/2/07, Craig D. Rice [EMAIL PROTECTED] 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
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
Robert Boyle wrote:
Either your firewall/router or the customer's firewall/router is
blocking PMTUD packets. I suspect an overzealous firewall admin
is blocking all icmp.
Which you can't do anything about if the overzealous firewall admin
is at the other end of the connection. My
On Thu, Aug 02, 2007, Jim Shankland wrote:
Linux has a nifty iptables option (clamp-mss-to-pmtu) to rewrite the
MSS in TCP SYN packets when forwarding a packet onto a link with
a lower MTU than the MSS in the packet. Works like a charm. If every
packet forwarding device on the Internet did
Adrian Chadd wrote:
On Thu, Aug 02, 2007, Jim Shankland wrote:
Linux has a nifty iptables option (clamp-mss-to-pmtu) to rewrite the
MSS in TCP SYN packets when forwarding a packet onto a link with
a lower MTU than the MSS in the packet. Works like a charm. If every
packet forwarding device
On Thu, 02 Aug 2007 18:33:16 PDT, Jim Shankland said:
Hmm; I've never actually heard of anybody doing PMTUD on non-TCP
traffic, though it's possible. Does anybody actually do it?
AIX 5.2 and earlier supported it for UDP (we're getting out of the AIX
business, so I can't speak to what 5.3
