A question for the reference
Spain, Dr. Jeffry A.
spainj at countryday.net
Tue Mar 6 02:23:46 UTC 2012
I tested this by capturing network traffic on a bind 9.9.0 recursive resolver. The commands 'rndc flush' followed by 'dig @localhost funnygamesite.com' resulted in the following:
1. A query to m.gtld-servers.net.
2. The same referral response that you got below.
3. A follow-up query 500 microseconds after the response to ns1.dnsbed.com.
4. Ns1.dnsbed.com then provided the answer (127.0.0.1).
Thus it appears that bind 9.9.0 is relying on the data in the Authority and Additional sections of the first query for the addresses of funnygamesite.com's authoritative name servers. It is not making any additional queries for the addresses of those name servers. Jeff.
Please see this case:
$ dig funnygamesite.com @k.gtld-servers.net
; <<>> DiG 9.7.3 <<>> funnygamesite.com @k.gtld-servers.net ;; global options: +cmd ;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 35540 ;; flags: qr rd; QUERY: 1, ANSWER: 0, AUTHORITY: 2, ADDITIONAL: 2 ;; WARNING: recursion requested but not available
;; QUESTION SECTION:
;funnygamesite.com. IN A
;; AUTHORITY SECTION:
funnygamesite.com. 172800 IN NS ns1.dnsbed.com.
funnygamesite.com. 172800 IN NS ns2.dnsbed.com.
;; ADDITIONAL SECTION:
ns1.dnsbed.com. 172800 IN A 18.104.22.168
ns2.dnsbed.com. 172800 IN A 22.214.171.124
;; Query time: 188 msec
;; SERVER: 126.96.36.199#53(188.8.131.52) ;; WHEN: Tue Mar 6 09:30:42 2012 ;; MSG SIZE rcvd: 110
When a resolver query funnygamesite.com from one of the gtld name servers, will the resolver use the reference (AUTHORITY SECTION and ADDITIONAL SECTION) directly? or it make another query for ns1.dnsbed.com and ns2.dnsbed.com and get the authorative answers for them?
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