IETF should be running on a clamped MSS. The only benefits of floating MTU upwards is an efficiency gain which is almost irrelevant for a text-mainly website of this nature.
It would be lovely if they could rely on the other end, but a governance body should be reachable all the time. -G (in my HO, and a private opinion unrelated to my employer) On 11/07/2012, at 1:35 PM, Mark Andrews wrote: > > In message <4ffccd9a.10...@m5p.com>, George Mitchell writes: >> So I was trying to browse the list of IETF mailing lists at www.ietf.org >> to see who might be interested in my failures to browse sites like >> yahoo.com and netflix.com following the onset of World IPv6 Day. >> >> Except that I can't browse www.ietf.org either. >> >> It did work previously. I have a packet capture of the failing "telnet >> www.ietf.org 80" session, if anyone is interested. It looks fine and >> proper, all the expected SYNs and ACKs as I sent my HTTP request, >> except for the failure to return any HTTP response. I'm running >> FreeBSD 9.0-STABLE. 8.2-STABLE also fails the same way. No doubt you >> can reach www.m5p.com over IPv6; it's been working for years. >> >> Would one of you be able to tell me which mailing should I be using? >> My apologies for the inappropriate message. -- George Mitchell >> -------------------------------------------------------------------- >> IETF IPv6 working group mailing list >> ipv6@ietf.org >> Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 >> -------------------------------------------------------------------- > > This sort of failure is usually a PMTUD failure. If you are using > a tunnel you need to ensure that your tunnel provider sends back > PTB's. The IETF servers do see the PTB's. www.ietf.org does work > over tunnels. > > You can test this theory by lowering the local mtu using "route > change -inet6 :: -mtu 1280" (from memory). This will change the > advertised mss from 1440. "route -n get -inet6 ::" will show you > the current values. > > -- > Mark Andrews, ISC > 1 Seymour St., Dundas Valley, NSW 2117, Australia > PHONE: +61 2 9871 4742 INTERNET: ma...@isc.org > -------------------------------------------------------------------- > IETF IPv6 working group mailing list > ipv6@ietf.org > Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 > -------------------------------------------------------------------- -------------------------------------------------------------------- IETF IPv6 working group mailing list ipv6@ietf.org Administrative Requests: https://www.ietf.org/mailman/listinfo/ipv6 --------------------------------------------------------------------
