Thanks .. I meant to include link to that article - appreciate you doing so :)
We don’t filter ICMPv6 on those servers and the problem we are pretty confident is ECMP related (as per what we learned from the Cloudflare blog) … need to set up some time to look deeper though as internally and on our own servers we’ve never been able to replicate the issue Cheers, Paul > On Oct 14, 2016, at 8:02 AM, JORDI PALET MARTINEZ > <[email protected]> wrote: > > The issue here is that customers (the ones that browse the broken web sites), > don’t know about MTU, ICMP, etc. > > So I guess is in your side as the “provider” of the content, who is the > interested party in making sure it works for “all” your possible customers. > > Up to now, every time I’ve seen this problem was just related to ICMPv6 being > filtered, as many folks do in IPv4 … > > > By the way, interesting article, I didn’t read it before: > https://blog.cloudflare.com/path-mtu-discovery-in-practice/ > > > Saludos, > Jordi > > > -----Mensaje original----- > De: <[email protected]> en nombre > de Paul Stewart <[email protected]> > Responder a: <[email protected]> > Fecha: viernes, 14 de octubre de 2016, 13:52 > Para: Mikael Abrahamsson <[email protected]> > CC: <[email protected]>, JORDI PALET MARTINEZ > <[email protected]> > Asunto: Re: contact with One & One ? > > At $$$job we run quite a bit of dual stack towards customers as an ISP > (mainly PPPoE) - our own public website fails the PTB test and quite honestly > we’ve never fixed it. it works for lots of customer/visitors but breaks for > others (and they fail back to IPv4) - we thought it was only external tunnel > visitors but have found out otherwise… never fully understood what was going > on and I keep meaning to look at it .. > > NGINX front ends load balanced via anycast … pretty standard Ubuntu > 16.04LTS setup on the server side. From what I’ve read it seems to be an > ECMP related problem like what CloudFlare published a blog about … > > Paul > >> On Oct 14, 2016, at 7:45 AM, Mikael Abrahamsson <[email protected]> wrote: >> >> On Fri, 14 Oct 2016, JORDI PALET MARTINEZ wrote: >> >>> I think is time to retire happy-eye-balls, it is the only way the people >>> will react to those issues! >> >> Happy eyeballs doesn't solve PMTU blackhole. >> >> So this is actually customer breakage occuring, but I imagine lots of ISPs >> are actually doing MSS re-write and/or announcing lower than 1500 MTU on the >> customer LAN, so even if a customer has PPPoE with 1492 MTU, they still >> won't see this problem. >> >> I have seen swedish authorities websites with same "won't-respond-to-PTB", >> no answer there either to fault reports. >> >> -- >> Mikael Abrahamsson email: [email protected] > > > > > > > ********************************************** > IPv4 is over > Are you ready for the new Internet ? > http://www.consulintel.es > The IPv6 Company > > This electronic message contains information which may be privileged or > confidential. The information is intended to be for the use of the > individual(s) named above. If you are not the intended recipient be aware > that any disclosure, copying, distribution or use of the contents of this > information, including attached files, is prohibited. > > >
