Hello, On Nov 22, 2013, at 9:45 , Francois Claire wrote:
>> Appears that you receive nxdomain from nameserver, see at the end of trace. >> > Indeed the g2.ebay.com. DNS server (66.211.167.40) answers thumbs.g.ebay.com. > with an NXDomain: > 14:13:38.023503 IP W.X.Y.Z.4994 > 66.211.167.40.53: 26515 [1au] A? > thumbs.g.ebay.com. (54) > 14:13:38.196462 IP 66.211.167.40.53 > W.X.Y.Z.4994: 26515 NXDomain*- 0/1/1 > (96) > > But when using dig, the g2.ebay.com. DNS server answers a CNAME record: > > $ dig @66.211.167.40 thumbs.g.ebay.com > > ; <<>> DiG 9.8.4-P2 <<>> @66.211.167.40 thumbs.g.ebay.com > ; (1 server found) > ;; global options: +cmd > ;; Got answer: > ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 58678 > ;; flags: qr aa rd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0 > ;; WARNING: recursion requested but not available > > ;; QUESTION SECTION: > ;thumbs.g.ebay.com. IN A > > ;; ANSWER SECTION: > thumbs.g.ebay.com. 60 IN CNAME c.ebay.georedirector.akadns.net. > > ;; Query time: 177 msec > ;; SERVER: 66.211.167.40#53(66.211.167.40) > ;; WHEN: Thu Nov 21 14:41:08 2013 > ;; MSG SIZE rcvd: 80 > > > So why is the powerDNS recursor receiving an NXDomain ? Is its query > malformed ? I don't know why your recursor is receiving NXDomain (mine does not, for example) - but this does not appear to be a PowerDNS Recursor issue. However, the g*.ebay.com servers are definitely broken. While the relevant query (dig +norec +noedns @66.211.167.40 thumbs.g.ebay.com A) returns the right CNAME for me, various other queries (replace A in the query with MX, ANY or even CNAME) yield NXDOMAIN. A recursor that receives NXDOMAIN when asking for a specific type is allowed to assume the NXDOMAIN applies to all other types. Given that they are broken like this, I'm not surprised they manage to reply NXDOMAIN to A-queries as well, in specific situations. If you have a contact at eBay, please let them know that their name servers are broken. I will also look into finding a contact. Kind regards, -- Peter van Dijk Netherlabs Computer Consulting BV - http://www.netherlabs.nl/
signature.asc
Description: Message signed with OpenPGP using GPGMail
_______________________________________________ Pdns-users mailing list [email protected] http://mailman.powerdns.com/mailman/listinfo/pdns-users
