Wow, I wasn't aware of that nuance. I have been making incorrect assumptions.
It doesn't make sense to me how DNS3.UIOWA.EDU can return the correct cached result for the NS records of sioux-center.k12.ia.us but an incorrect "norec" result. Doesn't specifying "no recursion" mean that it has to be either authoritative for that domain or have the entry cached in order to return any result at all? But the 'aa' bit is not set, which seems to me that it must have obtained the result from its cache. Frank -----Original Message----- From: Chris Buxton [mailto:cbux...@menandmice.com] Sent: Saturday, May 16, 2009 11:09 AM To: Frank Bulk Cc: bind-users@lists.isc.org Subject: Re: dig printout doesn't appear to match reality If you send the server a recursive query, you get an answer from its cache. If you sent it an iterative query, you get a referral from its authoritative zone. $ dig @DNS3.UIOWA.EDU sioux-center.k12.ia.us ns +noall +auth +norec ; <<>> DiG 9.4.3-P1 <<>> @DNS3.UIOWA.EDU sioux-center.k12.ia.us ns +noall +auth +norec ; (2 servers found) ;; global options: printcmd sioux-center.k12.ia.us. 28800 IN NS dns.mtcnet.net. sioux-center.k12.ia.us. 28800 IN NS ns1.netins.net. $ dig @DNS3.UIOWA.EDU sioux-center.k12.ia.us ns +noall +answer ; <<>> DiG 9.4.3-P1 <<>> @DNS3.UIOWA.EDU sioux-center.k12.ia.us ns +noall +answer ; (2 servers found) ;; global options: printcmd sioux-center.k12.ia.us. 83030 IN NS ns1.netins.net. sioux-center.k12.ia.us. 83030 IN NS ns2.mtcnet.net. sioux-center.k12.ia.us. 83030 IN NS ns1.mtcnet.net. Chris Buxton Professional Services Men & Mice On May 16, 2009, at 8:53 AM, Frank Bulk wrote: > It appears that dig is printing results that it attributes to the > wrong > server. > > While troubleshooting an inconsistent NS issue (upstream from us), a > trace > (at the end of this message) shows that DNS3.UIOWA.EDU listed two NS > records, when in fact, if you query DNS3.UIOWA.EDU for the domain in > question it returns three NS records. The results that were > returned belong > to either DNS-2.IASTATE.EDU or DNS2.ICN.STATE.ia.us. > > Why is dig attributing it to one NS server when it belongs to another? > > Regards, > > Frank > > = > = > = > = > = > = > ====================================================================== > == > nagios:/etc/cron.daily# dig +trace NS sioux-center.k12.ia.us > > ; <<>> DiG 9.5.1-P1 <<>> +trace NS sioux-center.k12.ia.us > ;; global options: printcmd > . 512780 IN NS b.root-servers.net. > . 512780 IN NS e.root-servers.net. > . 512780 IN NS f.root-servers.net. > . 512780 IN NS m.root-servers.net. > . 512780 IN NS g.root-servers.net. > . 512780 IN NS k.root-servers.net. > . 512780 IN NS l.root-servers.net. > . 512780 IN NS a.root-servers.net. > . 512780 IN NS h.root-servers.net. > . 512780 IN NS j.root-servers.net. > . 512780 IN NS d.root-servers.net. > . 512780 IN NS c.root-servers.net. > . 512780 IN NS i.root-servers.net. > ;; Received 500 bytes from 127.0.0.1#53(127.0.0.1) in 0 ms > > us. 172800 IN NS I.GTLD.BIZ. > us. 172800 IN NS J.GTLD.BIZ. > us. 172800 IN NS K.GTLD.BIZ. > us. 172800 IN NS B.GTLD.BIZ. > us. 172800 IN NS A.GTLD.BIZ. > us. 172800 IN NS C.GTLD.BIZ. > ;; Received 308 bytes from 128.8.10.90#53(d.root-servers.net) in 48 ms > > k12.ia.us. 7200 IN NS DNS-2.IASTATE.EDU. > k12.ia.us. 7200 IN NS DNS2.ICN.STATE.ia.us. > k12.ia.us. 7200 IN NS DNS3.UIOWA.EDU. > ;; Received 141 bytes from 156.154.96.126#53(I.GTLD.BIZ) in 97 ms > > sioux-center.k12.ia.us. 28800 IN NS ns1.netins.net. > sioux-center.k12.ia.us. 28800 IN NS dns.mtcnet.net. > ;; Received 109 bytes from 128.255.64.5#53(DNS3.UIOWA.EDU) in 18 ms > > sioux-center.k12.ia.us. 86400 IN NS ns2.mtcnet.net. > sioux-center.k12.ia.us. 86400 IN NS ns1.mtcnet.net. > sioux-center.k12.ia.us. 86400 IN NS ns1.netins.net. > ;; Received 159 bytes from 167.142.225.5#53(ns1.netins.net) in 9 ms > > _______________________________________________ > bind-users mailing list > bind-users@lists.isc.org > https://lists.isc.org/mailman/listinfo/bind-users _______________________________________________ bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
