1. ccTLD/cz/minimal-responses

について、ここに記述してください。

すっきりした返答だ。

2. root zone

%dnsq ns cz a.root-servers.net                                ~/dnsq/0304
2 cz:
267 bytes, 1+0+4+8 records, response, noerror
query: 2 cz
authority: cz 172800 NS a.ns.nic.cz
authority: cz 172800 NS b.ns.nic.cz
authority: cz 172800 NS c.ns.nic.cz
authority: cz 172800 NS d.ns.nic.cz
additional: a.ns.nic.cz 172800 A 194.0.12.1
additional: b.ns.nic.cz 172800 A 194.0.13.1
additional: c.ns.nic.cz 172800 A 194.0.14.1
additional: d.ns.nic.cz 172800 A 193.29.206.1
...

3. cz zone

%dnsq a a.ns.nic.cz 194.0.12.1                                ~/dnsq/0304
1 a.ns.nic.cz:
45 bytes, 1+1+0+0 records, response, authoritative, noerror
query: 1 a.ns.nic.cz
answer: a.ns.nic.cz 1800 A 194.0.12.1

4. だが

途中にnic.czゾーンがあって、同居しているので、注意。

%dnsq ns nic.cz 194.0.12.1                                    ~/dnsq/0304
2 nic.cz:
207 bytes, 1+3+0+6 records, response, authoritative, noerror
query: 2 nic.cz
answer: nic.cz 1800 NS a.ns.nic.cz
answer: nic.cz 1800 NS b.ns.nic.cz
answer: nic.cz 1800 NS d.ns.nic.cz
additional: a.ns.nic.cz 1800 A 194.0.12.1
...

この返答からも分かる。

%dnsq ns a.ns.nic.cz 194.0.12.1                               ~/dnsq/0304
2 a.ns.nic.cz:
76 bytes, 1+0+1+0 records, response, authoritative, noerror
query: 2 a.ns.nic.cz
authority: nic.cz 1800 SOA a.ns.nic.cz hostmaster.nic.cz 1521492002 10800 3600 1209600 7200

5. こんなサーバーも含まれている

c.ns.nic.cz は nic.czのゾーン(権威)サーバではない!

%dnsq a a.ns.nic.cz 194.0.14.1                                ~/dnsq/0304
1 a.ns.nic.cz:
207 bytes, 1+1+3+5 records, response, authoritative, noerror
query: 1 a.ns.nic.cz
answer: a.ns.nic.cz 1800 A 194.0.12.1
authority: nic.cz 1800 NS b.ns.nic.cz
authority: nic.cz 1800 NS a.ns.nic.cz
authority: nic.cz 1800 NS d.ns.nic.cz
additional: a.ns.nic.cz 1800 28 \040\001\006x\000\017\000\000\000\000\000\000\000\000\000\001
additional: b.ns.nic.cz 1800 A 194.0.13.1
additional: b.ns.nic.cz 1800 28 \040\001\006x\000\020\000\000\000\000\000\000\000\000\000\001
additional: d.ns.nic.cz 1800 A 193.29.206.1
additional: d.ns.nic.cz 1800 28 \040\001\006x\000\001\000\000\000\000\000\000\000\000\000\001

この返事はnic.czの権威サーバーとして設定されていることを示す。w

%dnsq ns nic.cz 194.0.14.1                                    ~/dnsq/0304
2 nic.cz:
207 bytes, 1+3+0+6 records, response, authoritative, noerror
query: 2 nic.cz
answer: nic.cz 1800 NS b.ns.nic.cz
answer: nic.cz 1800 NS d.ns.nic.cz
answer: nic.cz 1800 NS a.ns.nic.cz
additional: a.ns.nic.cz 1800 A 194.0.12.1
additional: a.ns.nic.cz 1800 28 \040\001\006x\000\017\000\000\000\000\000\000\000\000\000\001
additional: b.ns.nic.cz 1800 A 194.0.13.1
additional: b.ns.nic.cz 1800 28 \040\001\006x\000\020\000\000\000\000\000\000\000\000\000\001
additional: d.ns.nic.cz 1800 A 193.29.206.1
additional: d.ns.nic.cz 1800 28 \040\001\006x\000\001\000\000\000\000\000\000\000\000\000\001