Came across this one right now (21:48 PDT (UTC-0700)) while trying to look up some tracking information on an Ontrac package I have. Ontrac uses WorldNIC/Netsol as their authoritative nameservers. I wasn't able to resolve www.ontrac.com from my Comcast connection at home (Mountain View, CA), while I saw intermittent DNS failures when trying to do resolution from my VPS (Sylmar, CA), so I poked at things a bit. First from my VPS: $ host www.ontrac.com www.ontrac.com has address 12.38.237.1 Host www.ontrac.com not found: 3(NXDOMAIN) And now from home: $ host www.ontrac.com ;; connection timed out; no servers could be reached $ dig @a.gtld-servers.net ns ontrac.com ; <<>> DiG 9.8.4-P2 <<>> @a.gtld-servers.net ns ontrac.com ; (1 server found) ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33697 ;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2 ;; WARNING: recursion requested but not available ;; QUESTION SECTION: ;ontrac.com. IN NS ;; AUTHORITY SECTION: ontrac.com. 172800 IN NS ns89.worldnic.com. ontrac.com. 172800 IN NS ns90.worldnic.com. ;; ADDITIONAL SECTION: ns89.worldnic.com. 172800 IN A 205.178.190.45 ns90.worldnic.com. 172800 IN A 206.188.198.45 ;; Query time: 97 msec ;; SERVER: 192.5.6.30#53(192.5.6.30) ;; WHEN: Wed May 15 21:38:12 2013 ;; MSG SIZE rcvd: 107 $ dig @205.178.190.45 any www.ontrac.com ; <<>> DiG 9.8.4-P2 <<>> @205.178.190.45 any www.ontrac.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached $ dig @205.188.198.45 any www.ontrac.com ; <<>> DiG 9.8.4-P2 <<>> @205.188.198.45 any www.ontrac.com ; (1 server found) ;; global options: +cmd ;; connection timed out; no servers could be reached $ mtr 205.178.190.45 Packets Pings Host Loss% Snt Rcv Last Avg Best Wrst 1. gw.home.lan 0.0% 11 11 0.3 0.3 0.2 0.4 2. c-67-180-84-1.hsd1.ca.comcast.net 0.0% 11 11 30.1 22.8 14.0 30.1 3. te-0-0-0-12-ur05.santaclara.ca.sfba.comcast 0.0% 11 11 9.3 10.3 9.3 11.2 4. te-1-1-0-13-ar01.sfsutro.ca.sfba.comcast.ne 0.0% 11 11 15.2 13.3 10.6 15.8 5. he-1-5-0-0-cr01.sanjose.ca.ibone.comcast.ne 0.0% 11 11 21.0 21.7 20.5 23.6 6. er1-tengig2-4.sanjoseequinix.savvis.net 0.0% 11 11 12.9 13.0 11.9 14.1 7. 206.28.98.70 0.0% 11 11 14.5 19.2 11.8 80.0 8. cr2-tengig0-7-3-0.sanfrancisco.savvis.net 0.0% 11 11 14.7 21.6 14.7 63.0 9. cr1-ten-0-13-1-0.dck.savvis.net 0.0% 11 11 91.6 91.6 90.0 94.1 10. hr1-tengig-2-0-0.sterling2dc2.savvis.net 0.0% 11 11 92.1 90.9 90.2 92.1 11. ??? $ mtr 205.188.198.45 Packets Pings Host Loss% Snt Rcv Last Avg Best Wrst 1. gw.home.lan 0.0% 11 11 0.4 0.3 0.2 0.4 2. c-67-180-84-1.hsd1.ca.comcast.net 0.0% 11 11 31.3 26.8 16.3 39.3 3. te-0-0-0-12-ur05.santaclara.ca.sfba.comcast 0.0% 11 11 15.4 12.5 9.8 15.6 4. te-1-1-0-1-ar01.sfsutro.ca.sfba.comcast.net 0.0% 11 11 14.7 15.2 11.4 28.3 5. he-1-7-0-0-cr01.sanjose.ca.ibone.comcast.ne 0.0% 11 11 21.6 19.8 16.2 24.1 6. be-10-pe02.11greatoaks.ca.ibone.comcast.net 0.0% 11 11 16.4 16.7 15.1 19.4 7. 66.185.150.117 0.0% 11 11 16.7 17.2 14.2 32.7 8. bb1-sjg-xe-1-2-0.atdn.net 0.0% 11 11 16.5 16.0 14.5 17.5 9. bb2-ash-xe-0-0-3.atdn.net 0.0% 11 11 86.9 86.8 85.1 90.3 10. pop1-ash-xe-1-0-0.atdn.net 0.0% 11 11 89.0 86.2 84.7 89.0 11. dar1-dtc-xe-1-2-0.atdn.net 0.0% 11 11 87.6 90.0 84.4 105.7 12. gear1-dtc-lag0.net.aol.com 0.0% 11 11 86.0 86.2 84.8 90.1 13. edge4-dtc-ae0-staging.net.aol.com 0.0% 11 11 86.0 90.7 85.1 133.3 14. ??? Obviously I don't have return path traces. I repeated the digs from my VPS, and they work but only intermittently. So I'm guessing some kind of GSLB or network interface round-robining may be impacting things, but only via some routes/paths. Sorry if I've forgotten some information or a step, doing too many things at once right now... :-) -- | Jeremy Chadwick jdc@koitsu.org | | UNIX Systems Administrator http://jdc.koitsu.org/ | | Mountain View, CA, US | | Making life hard for others since 1977. PGP 4BD6C0CB |