Monday, October 19, 2009

MyDNS strangeness:

erl@cumulus:~/src/mydns-1.2.8$ dig www.voxi.com

; <<>> DiG 9.5.1-P2 <<>> www.voxi.com
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 15541 ;; flags: qr rd ra; QUERY: 1, ANSWER: 3, AUTHORITY: 0, ADDITIONAL: 0 ;; WARNING: Messages has 422 extra bytes at end ;; QUESTION SECTION: ;www.voxi.com. IN A ;; ANSWER SECTION: www.voxi.com. 66720 IN CNAME www.lewin.nu. www.lewin.nu. 62093 IN CNAME sol.lewin.nu. sol.lewin.nu. 62093 IN A 83.227.241.4 ;; Query time: 15 msec ;; SERVER: 172.16.1.21#53(172.16.1.21) erl@cumulus:~/src/mydns-1.2.8$ dig www.lewin.nu ; <<>> DiG 9.5.1-P2 <<>> www.lewin.nu
;; global options: printcmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3984 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 1, ADDITIONAL: 1 ;; QUESTION SECTION: ;www.lewin.nu. IN A ;; ANSWER SECTION: www.lewin.nu. 86400 IN A 172.16.1.21 ;; AUTHORITY SECTION: lewin.nu. 86400 IN NS ns.lewin.nu. ;; ADDITIONAL SECTION: ns.lewin.nu. 86400 IN A 172.16.1.21 ;; Query time: 5 msec ;; SERVER: 172.16.1.21#53(172.16.1.21)
So, the first query tells me that www.voxi.com is CNAME www.lewin.nu which is CNAME sol.lewin.nu, while the second query says that www.lewin.nu is IN A 172.16.1.21. How can the same server give me two different answers for www.lewin.nu?

(while rebuilding mydns with debug enabled, installed package manpages-dev)

After debug-compiling mydns, it looks like the above query results in a recursive query, which in turn asks the bredbandsbolaget DNS server.

Found the problem - the www.voxi.com domain was not marked as 'active' in mydns' database. We should de-activate it when the new internet DNS server is online.
I'll continue debugging this tomorrow.

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