DNS/KnotResolver/nodataについて、ここに記述してください。
$ kdig -t txt b.c.d.qmail.jp @127.0.0.3
;; ->>HEADER<<- opcode: QUERY; status: NOERROR; id: 41477 ;; Flags: qr rd ra; QUERY: 1; ANSWER: 1; AUTHORITY: 0; ADDITIONAL: 0 ;; QUESTION SECTION: ;; b.c.d.qmail.jp. IN TXT ;; ANSWER SECTION: b.c.d.qmail.jp. 86400 IN TXT "b.c.d.qmail.jp" ;; Received 59 B ;; Time 2015-10-25 18:02:37 JST ;; From 127.0.0.3@53(UDP) in 407.3 ms
$ kdig -t ns d.qmail.jp @127.0.0.3
;; ->>HEADER<<- opcode: QUERY; status: NXDOMAIN; id: 17639 ;; Flags: qr rd ra; QUERY: 1; ANSWER: 0; AUTHORITY: 1; ADDITIONAL: 0 ;; QUESTION SECTION: ;; d.qmail.jp. IN NS ;; AUTHORITY SECTION: qmail.jp. 2544 IN SOA f.ns.qmail.jp. hostmaster.m.qmail.jp. 1445762887 16384 2048 1048576 2560 ;; Received 82 B ;; Time 2015-10-25 18:02:53 JST ;; From 127.0.0.3@53(UDP) in 0.2 ms
$ kdig -t txt c.d.qmail.jp @127.0.0.3
;; ->>HEADER<<- opcode: QUERY; status: NXDOMAIN; id: 46367 ;; Flags: qr rd ra; QUERY: 1; ANSWER: 0; AUTHORITY: 1; ADDITIONAL: 0 ;; QUESTION SECTION: ;; c.d.qmail.jp. IN TXT ;; AUTHORITY SECTION: d.qmail.jp. 2560 IN SOA a.ns.d.qmail.jp. hostmaster.d.qmail.jp. 1444734355 16384 2048 1048576 2560 ;; Received 82 B ;; Time 2015-10-25 18:04:22 JST ;; From 127.0.0.3@53(UDP) in 135.9 ms
$ kdig -t ns d.qmail.jp @127.0.0.3
;; ->>HEADER<<- opcode: QUERY; status: NOERROR; id: 37549 ;; Flags: qr rd ra; QUERY: 1; ANSWER: 1; AUTHORITY: 0; ADDITIONAL: 0 ;; QUESTION SECTION: ;; d.qmail.jp. IN NS ;; ANSWER SECTION: d.qmail.jp. 259116 IN NS a.ns.d.qmail.jp. ;; Received 47 B ;; Time 2015-10-25 18:05:46 JST ;; From 127.0.0.3@53(UDP) in 0.2 ms
[plan] plan 'b.c.d.qmail.jp.' type 'TXT' [resl] => root priming query [plan] plan '.' type 'NS' [resl] => querying: '198.41.0.4' score: 10 zone cut: '.' m12n: '.' type: 'NS' [iter] <= rcode: NOERROR [resl] => querying: '192.5.5.241' score: 10 zone cut: '.' m12n: 'JP.' type: 'NS' [iter] <= referral response, follow [resl] => querying: '203.119.1.1' score: 10 zone cut: 'jp.' m12n: 'QMaiL.JP.' type: 'NS' [iter] <= referral response, follow [resl] => querying: '14.192.44.5' score: 10 zone cut: 'qmail.jp.' m12n: 'D.qmAiL.JP.' type: 'NS' [iter] <= rcode: NXDOMAIN [iter] <= found cut, retrying with non-minimized name [ pc ] => answer cached for TTL=900 [resl] => querying: '14.192.44.5' score: 58 zone cut: 'qmail.jp.' m12n: 'B.C.d.QMAil.JP.' type: 'TXT' [iter] <= rcode: NOERROR [resl] finished: 4, queries: 2, mempool: 16392 B [plan] plan 'd.qmail.jp.' type 'NS' [ pc ] => satisfied from cache [iter] <= rcode: NXDOMAIN [resl] finished: 4, queries: 1, mempool: 16392 B
define d.qmail.jp NS as poison
[plan] plan 'c.d.qmail.jp.' type 'TXT' [resl] => querying: '14.192.44.5' score: 58 zone cut: 'qmail.jp.' m12n: 'c.D.qMaIL.jp.' type: 'TXT' [iter] <= referral response, follow [resl] => querying: '14.192.44.29' score: 10 zone cut: 'd.qmail.jp.' m12n: 'c.D.QmaIl.Jp.' type: 'TXT' [iter] <= rcode: NXDOMAIN [ pc ] => answer cached for TTL=900 [resl] finished: 4, queries: 1, mempool: 16392 B [plan] plan 'd.qmail.jp.' type 'NS' [ rc ] => satisfied from cache [iter] <= rcode: NOERROR [resl] finished: 4, queries: 1, mempool: 16392 B