1. watchWWW/yahoo.co.jp

について、ここに記述してください。

yahoo.co.jp.            86400   IN      NS      ns11.yahoo.co.jp.
yahoo.co.jp.            86400   IN      NS      ns12.yahoo.co.jp.
yahoo.co.jp.            86400   IN      NS      ns02.yahoo.co.jp.
yahoo.co.jp.            86400   IN      NS      ns01.yahoo.co.jp.

$ dnsq a www.yahoo.co.jp 118.151.254.133
1 www.yahoo.co.jp:
133 bytes, 1+1+2+2 records, response, authoritative, noerror
query: 1 www.yahoo.co.jp
answer: www.yahoo.co.jp 900 CNAME edge12.g.yimg.jp
authority: g.yimg.jp 900 NS gns02.yahoo.co.jp
authority: g.yimg.jp 900 NS gns12.yahoo.co.jp
additional: gns02.yahoo.co.jp 900 A 118.151.254.148
additional: gns12.yahoo.co.jp 900 A 124.83.255.100

CNAMEの先(本名)を追わなくなったのはよい。-- ToshinoriMaeno 2018-11-28 06:29:52

$ dnsq a edge12.g.yimg.jp a.dns.jp
1 edge12.g.yimg.jp:
183 bytes, 1+0+4+4 records, response, noerror
query: 1 edge12.g.yimg.jp
authority: yimg.jp 86400 NS ns11.yahoo.co.jp
authority: yimg.jp 86400 NS ns02.yahoo.co.jp
authority: yimg.jp 86400 NS ns01.yahoo.co.jp
authority: yimg.jp 86400 NS ns12.yahoo.co.jp
additional: ns01.yahoo.co.jp 86400 A 118.151.254.133
additional: ns02.yahoo.co.jp 86400 A 118.151.254.149
additional: ns11.yahoo.co.jp 86400 A 124.83.255.37
additional: ns12.yahoo.co.jp 86400 A 124.83.255.101

同居なのに、CNAMEの先を答えない。(それが悪いということではない。) -- ToshinoriMaeno 2018-11-28 06:19:58

理由はこれ。 g.yimg.jp が別ゾーン /yimg.jp

$ dnsq a edge12.g.yimg.jp 118.151.254.133
1 edge12.g.yimg.jp:
115 bytes, 1+0+2+2 records, response, noerror
query: 1 edge12.g.yimg.jp
authority: g.yimg.jp 900 NS gns02.yahoo.co.jp
authority: g.yimg.jp 900 NS gns12.yahoo.co.jp
additional: gns02.yahoo.co.jp 900 A 118.151.254.148
additional: gns12.yahoo.co.jp 900 A 124.83.255.100

$ dnsq a edge12.g.yimg.jp 118.151.254.148
1 edge12.g.yimg.jp:
50 bytes, 1+1+0+0 records, response, authoritative, noerror
query: 1 edge12.g.yimg.jp
answer: edge12.g.yimg.jp 60 A 182.22.25.252