Hello, I found that some queries have got the response which has additional section, but some haven't. For example, this query with www.google.com got the answer with additional section set:
$ dig www.google.com ; <<>> DiG 9.6.1-P2 <<>> www.google.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 57737 ;; flags: qr rd ra; QUERY: 1, ANSWER: 7, AUTHORITY: 4, ADDITIONAL: 1 ;; QUESTION SECTION: ;www.google.com. IN A ;; ANSWER SECTION: www.google.com. 604672 IN CNAME www.l.google.com. www.l.google.com. 172 IN A 74.125.71.104 www.l.google.com. 172 IN A 74.125.71.105 www.l.google.com. 172 IN A 74.125.71.106 www.l.google.com. 172 IN A 74.125.71.147 www.l.google.com. 172 IN A 74.125.71.99 www.l.google.com. 172 IN A 74.125.71.103 ;; AUTHORITY SECTION: google.com. 172672 IN NS ns4.google.com. google.com. 172672 IN NS ns2.google.com. google.com. 172672 IN NS ns3.google.com. google.com. 172672 IN NS ns1.google.com. ;; ADDITIONAL SECTION: ns1.google.com. 345563 IN A 216.239.32.10 ;; Query time: 0 msec ;; SERVER: 119.147.163.133#53(119.147.163.133) ;; WHEN: Thu Sep 1 10:50:45 2011 ;; MSG SIZE rcvd: 236 But this same query get the answer without additional section: $ dig www.google.com ; <<>> DiG 9.6.1-P2 <<>> www.google.com ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 33219 ;; flags: qr rd ra; QUERY: 1, ANSWER: 7, AUTHORITY: 4, ADDITIONAL: 0 ;; QUESTION SECTION: ;www.google.com. IN A ;; ANSWER SECTION: www.google.com. 604800 IN CNAME www.l.google.com. www.l.google.com. 300 IN A 74.125.71.106 www.l.google.com. 300 IN A 74.125.71.147 www.l.google.com. 300 IN A 74.125.71.99 www.l.google.com. 300 IN A 74.125.71.103 www.l.google.com. 300 IN A 74.125.71.104 www.l.google.com. 300 IN A 74.125.71.105 ;; AUTHORITY SECTION: google.com. 172800 IN NS ns4.google.com. google.com. 172800 IN NS ns3.google.com. google.com. 172800 IN NS ns1.google.com. google.com. 172800 IN NS ns2.google.com. ;; Query time: 399 msec ;; SERVER: 119.147.163.133#53(119.147.163.133) ;; WHEN: Thu Sep 1 10:48:36 2011 ;; MSG SIZE rcvd: 220 My question is under what condition the nameserver answers the query with additional section set? Thank you. _______________________________________________ Please visit https://lists.isc.org/mailman/listinfo/bind-users to unsubscribe from this list bind-users mailing list bind-users@lists.isc.org https://lists.isc.org/mailman/listinfo/bind-users
