TTL is varying across nameservers

[Robert M. Stockmann]

There is something strange going on with the TTL
of my domain across nameservers on the internet.

This is how its configured on ns1.stokkie.net and ns2.stokkie.net :

$ dig +norecurse +ttlid stokkie.net @84.87.53.162

; <<>> DiG 9.8.1 <<>> +norecurse +ttlid stokkie.net @84.87.53.162
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 54209
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            86400   IN      A       84.87.53.162

;; AUTHORITY SECTION:
stokkie.net.            86400   IN      NS      ns2.stokkie.net.
stokkie.net.            86400   IN      NS      ns1.stokkie.net.

;; ADDITIONAL SECTION:
ns1.stokkie.net.        86400   IN      A       84.87.53.162
ns2.stokkie.net.        86400   IN      A       92.67.169.193

;; Query time: 2 msec
;; SERVER: 84.87.53.162#53(84.87.53.162)
;; WHEN: Sun Sep 25 07:40:40 2022
;; MSG SIZE  rcvd: 113

$ 

$ dig +norecurse +ttlid stokkie.net @92.67.169.193 

; <<>> DiG 9.8.1 <<>> +norecurse +ttlid stokkie.net @92.67.169.193
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 15700
;; flags: qr aa; QUERY: 1, ANSWER: 1, AUTHORITY: 2, ADDITIONAL: 2

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            86400   IN      A       84.87.53.162

;; AUTHORITY SECTION:
stokkie.net.            86400   IN      NS      ns1.stokkie.net.
stokkie.net.            86400   IN      NS      ns2.stokkie.net.

;; ADDITIONAL SECTION:
ns1.stokkie.net.        86400   IN      A       84.87.53.162
ns2.stokkie.net.        86400   IN      A       92.67.169.193

;; Query time: 13 msec
;; SERVER: 92.67.169.193#53(92.67.169.193)
;; WHEN: Sun Sep 25 07:41:33 2022
;; MSG SIZE  rcvd: 113

$ 

Here the nameserver of my ADSL ISP, resolver1.kpn.net :

$ dig +ttlid stokkie.net @194.151.228.18

; <<>> DiG 9.8.1 <<>> +ttlid stokkie.net @194.151.228.18
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 47231
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            79291   IN      A       84.87.53.162

;; Query time: 8 msec
;; SERVER: 194.151.228.18#53(194.151.228.18)
;; WHEN: Sun Sep 25 07:43:40 2022
;; MSG SIZE  rcvd: 45

$ 

Here the nameserver of my ADSL ISP, resolver2.kpn.net :

$ dig +ttlid stokkie.net @194.151.228.34

; <<>> DiG 9.8.1 <<>> +ttlid stokkie.net @194.151.228.34
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 55404
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            86400   IN      A       84.87.53.162

;; Query time: 28 msec
;; SERVER: 194.151.228.34#53(194.151.228.34)
;; WHEN: Sun Sep 25 07:44:22 2022
;; MSG SIZE  rcvd: 45

$ 

Here the public DNS server of Google :

$ dig +ttlid stokkie.net @8.8.8.8

; <<>> DiG 9.8.1 <<>> +ttlid stokkie.net @8.8.8.8
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 29668
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            21599   IN      A       84.87.53.162

;; Query time: 2033 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Sep 25 07:46:03 2022
;; MSG SIZE  rcvd: 45

$

Here's the second time Google :

$ dig +ttlid stokkie.net @8.8.8.8

; <<>> DiG 9.8.1 <<>> +ttlid stokkie.net @8.8.8.8
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 3080
;; flags: qr rd ra; QUERY: 1, ANSWER: 1, AUTHORITY: 0, ADDITIONAL: 0

;; QUESTION SECTION:
;stokkie.net.                   IN      A

;; ANSWER SECTION:
stokkie.net.            21600   IN      A       84.87.53.162

;; Query time: 23 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Sun Sep 25 07:46:18 2022
;; MSG SIZE  rcvd: 45

$ 


Is this proper behavior ?


-- 
Robert M. Stockmann - RHCE
Network Engineer - UNIX/Linux Specialist
crashrecovery.org  stock at stokkie.net