1. watchNS/agm.co.jp
%dnsq ns agm.co.jp a.dns.jp
2 agm.co.jp: 86 bytes, 1+0+2+0 records, response, noerror query: 2 agm.co.jp authority: agm.co.jp 86400 NS ns.center.web.ad.jp authority: agm.co.jp 86400 NS ns.xsp.fenics.jp
こっちの返事がおかしい。
%dig -t ns agm.co.jp @ns.center.web.ad.jp
; <<>> DiG 9.9.0 <<>> -t ns agm.co.jp @ns.center.web.ad.jp ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 6517 ;; flags: qr aa rd ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 3 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;agm.co.jp. IN NS ;; ANSWER SECTION: agm.co.jp. 3600 IN NS ns.xsp.fenics.jp. agm.co.jp. 3600 IN NS ns.center.web.ad.jp. ;; ADDITIONAL SECTION: ns.xsp.fenics.jp. 251 IN A 202.248.234.17 ns.center.web.ad.jp. 86400 IN A 202.248.0.34 ;; Query time: 7 msec ;; SERVER: 202.248.0.34#53(202.248.0.34) ;; WHEN: Tue May 26 19:22:53 2015 ;; MSG SIZE rcvd: 129
キャッシュされているデータもadditionalにつけてくる。
- additional を信用してはいけないという理由のひとつ。(ここでは外部名だから、当然だが)
-- ToshinoriMaeno 2015-05-26 10:27:22
%dig +norec -t ns agm.co.jp @ns.center.web.ad.jp
; <<>> DiG 9.9.0 <<>> +norec -t ns agm.co.jp @ns.center.web.ad.jp ;; global options: +cmd ;; Got answer: ;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 12290 ;; flags: qr aa ra; QUERY: 1, ANSWER: 2, AUTHORITY: 0, ADDITIONAL: 3 ;; OPT PSEUDOSECTION: ; EDNS: version: 0, flags:; udp: 4096 ;; QUESTION SECTION: ;agm.co.jp. IN NS ;; ANSWER SECTION: agm.co.jp. 3600 IN NS ns.center.web.ad.jp. agm.co.jp. 3600 IN NS ns.xsp.fenics.jp. ;; ADDITIONAL SECTION: ns.xsp.fenics.jp. 127 IN A 202.248.234.17 ns.center.web.ad.jp. 86400 IN A 202.248.0.34 ;; Query time: 7 msec ;; SERVER: 202.248.0.34#53(202.248.0.34) ;; WHEN: Tue May 26 19:24:57 2015 ;; MSG SIZE rcvd: 129