1. DNS/リゾルバー/動作/tkix.net

net TLD は in-bailiwick NS には Additional A/AAAAが必須だとか。

1.1. delegation

$ dig -t ns tkix.net @a.gtld-servers.net

; <<>> DiG 9.16.1-Ubuntu <<>> -t ns tkix.net @a.gtld-servers.net
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 4027
;; flags: qr rd cd; QUERY: 1, ANSWER: 0, AUTHORITY: 3, ADDITIONAL: 4
;; WARNING: recursion requested but not available

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
; NSID: 6e 6e 6e 31 2d 73 66 6f 33 ("nnn1-sfo3")
;; QUESTION SECTION:
;tkix.net.                      IN      NS

;; AUTHORITY SECTION:
tkix.net.               172800  IN      NS      ns.tkix.net.
tkix.net.               172800  IN      NS      fake.spam18.net.
tkix.net.               172800  IN      NS      fake2.spam18.net.

;; ADDITIONAL SECTION:
ns.tkix.net.            172800  IN      A       150.42.6.4
fake.spam18.net.        172800  IN      A       14.192.44.1
fake2.spam18.net.       172800  IN      A       14.192.44.1

;; Query time: 104 msec
;; SERVER: 192.5.6.30#53(192.5.6.30)
;; WHEN: 土  6月 05 10:32:23 JST 2021
;; MSG SIZE  rcvd: 161

1.2. txt

• cf1111.tcpreplay.net の調査からすれば、以下の返答はおかしくない。

$ dig -t txt tkix\.net @1.1.1.1

; <<>> DiG 9.16.1-Ubuntu <<>> -t txt tkix.net @1.1.1.1
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 43491
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 1232
; NSID: 32 32 6d 31 39 39 ("22m199")
;; QUESTION SECTION:
;tkix.net.                      IN      TXT

;; ANSWER SECTION:
tkix.net.               30      IN      TXT     "Do_you_believe_this_zone?"

;; Query time: 15 msec
;; SERVER: 1.1.1.1#53(1.1.1.1)
;; WHEN: 土  6月 05 10:23:16 JST 2021
;; MSG SIZE  rcvd: 85

1.3. 8.8.8.8/9.9.9.9

ときどき、こうなる。

$ dig -t txt tkix.net @9.9.9.9

; <<>> DiG 9.16.1-Ubuntu <<>> -t txt tkix.net @9.9.9.9
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 30980
;; flags: qr rd ra cd; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 1

;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
; NSID: 72 65 73 32 30 30 2e 6e 72 74 2e 72 72 64 6e 73 2e 70 63 68 2e 6e 65 74 ("res200.nrt.rrdns.pch.net")
;; QUESTION SECTION:
;tkix.net.                      IN      TXT

;; ANSWER SECTION:
tkix.net.               30      IN      TXT     "Do_you_believe_this_zone?"

;; Query time: 195 msec
;; SERVER: 9.9.9.9#53(9.9.9.9)
;; WHEN: 土  6月 05 10:58:39 JST 2021
;; MSG SIZE  rcvd: 103