TLD/com/nstld.comについて、ここに記述してください。
http://www.buddyns.com/delegation-lab/nstld.com
com TLDのNS(A)が 192.54.112.30 だとして、{この部分が問題なのだが}
rootからの返事では ../com のNSが[a-m].gtld-servers.netだということだが、
additionalはglueではない。捨てるのが安全だ。-- ToshinoriMaeno 2016-04-10 09:50:38
$ dnsq a av1.nstld.com 192.54.112.30
1 av1.nstld.com: 275 bytes, 1+0+4+8 records, response, noerror query: 1 av1.nstld.com authority: nstld.com 172800 NS av1.nstld.com authority: nstld.com 172800 NS av2.nstld.com authority: nstld.com 172800 NS av3.nstld.com authority: nstld.com 172800 NS av4.nstld.com additional: av1.nstld.com 172800 A 192.42.177.30 additional: av1.nstld.com 172800 28 \040\001\005\000\001$\000\000\000\000\000\000\000\000\0000 additional: av2.nstld.com 172800 A 192.42.178.30 additional: av2.nstld.com 172800 28 \040\001\005\000\001%\000\000\000\000\000\000\000\000\0000 additional: av3.nstld.com 172800 A 192.82.133.30 additional: av3.nstld.com 172800 28 \040\001\005\000\001&\000\000\000\000\000\000\000\000\0000 additional: av4.nstld.com 172800 A 192.82.134.30 additional: av4.nstld.com 172800 28 \040\001\005\000\001'\000\000\000\000\000\000\000\000\0000
ゾーン権威サーバが返すAレコードのTTLが心配だ。(確認手順は省略)
$ dnsq ns nstld.com 192.42.177.30 2 nstld.com: 275 bytes, 1+4+0+8 records, response, authoritative, noerror query: 2 nstld.com answer: nstld.com 86400 NS av3.nstld.com answer: nstld.com 86400 NS av1.nstld.com answer: nstld.com 86400 NS av2.nstld.com answer: nstld.com 86400 NS av4.nstld.com additional: av3.nstld.com 300 A 192.82.133.30 additional: av3.nstld.com 300 28 \040\001\005\000\001&\000\000\000\000\000\000\000\000\0000 additional: av1.nstld.com 300 A 192.42.177.30 additional: av1.nstld.com 300 28 \040\001\005\000\001$\000\000\000\000\000\000\000\000\0000 additional: av2.nstld.com 300 A 192.42.178.30 additional: av2.nstld.com 300 28 \040\001\005\000\001%\000\000\000\000\000\000\000\000\0000 additional: av4.nstld.com 300 A 192.82.134.30 additional: av4.nstld.com 300 28 \040\001\005\000\001'\000\000\000\000\000\000\000\000\0000