Many thanks to Jared for jumping on this so quickly off-list, it's much appreciated and hopefully we're getting towards a solution now. Bryn
On 04/09/2012 15:12, "Jared Mauch" <ja...@puck.nether.net> wrote: >I know a few folks from NTT have looked into this. If someone >from KPN would get in touch with Bryn I'm sure the issue could be >quickly resolved. > >- Jared > >On Sep 4, 2012, at 9:18 AM, Brandt, Ralph wrote: > >> I will bet that will bet that within 48 hours of you checking and >> posting this the problem will mysteriously go away. >> >> >> >> Ralph Brandt >> Mechanicsburg PA 17055 >> >> -----Original Message----- >> From: Bryn Sadler [mailto:bryn.sad...@essensys.co.uk] >> Sent: Tuesday, September 04, 2012 9:02 AM >> To: nanog@nanog.org >> Subject: Strange Reachability Issue >> >> Hello all, >> >> I was wondering if anyone might be able to share their thoughts on a >> strange issue we're experiencing with NTT at the moment. We're AS48273 >> and are advertising a prefix 94.198.184.0/21 through AS 8190 (single >> upstream provider at the moment). We've been doing this for some years >> now, and all has been fine. The last few days we seem to have >> disappeared from NTT's worldwide routing tables, with the exception of >> Europe. If we use their looking glass to query any NTT european router >> we can see the prefix, being learned via AS 286 then AS 8190, as >> expected. If we look at any other router outside of europe, there is >> simply no entry for that prefix. Elsewhere in the world we seem to be >> fine, we're in every other network I've looked at and general >> reachability is fine. >> >> First step was to contact the NTT NOC, and they've confirmed that >> there's no Internal routing/config issue on their network, but that they >> cannot discuss their peering arrangements due to NDAs. We've also picked >> it up with KPN (AS 286), who have verified that the prefix is visible >> throughout their network (true), and that they are advertising it to >> NTT. One thing of note is that Global Crossing are learning our prefix >> from KPN as well, and the prefix is showing fine in their global tables. >> >> We seem to be caught in the classic finger pointing scenario, but I >> can't get my head around why the prefix is visible in NTT Europe, but >> not anywhere else, unless they have a config error somewhere on their >> network. We've checked a few of the routes from AS 8190 and they are in >> the NTT global tables just fine, and at least in Europe they seem to >> have the same community values etc. We're still following on with NTT, >> but can anyone offer some wisdom for new avenues to pursue? >> >> Thanks for your help, >> >> Bryn Sadler >> >> >> This message has been scanned for viruses by essensys mailcontrol >> >
