The first thing to understand about DNS is that public DNS servers will cache their entries until the TTL (time to live) value expires.
Most (if not all) TLD providers normally set this value at 172800 seconds (which is 48 hours).
However the best thing you can do is learn how to find a domains Glue records. These are located in the zone files of your TLD.
So imagine I want to find the Glue records for google.com. How would you do this?
First of all find the authoritative servers for the com. domain using DIG.
C:\Users\timdu>dig ns com.
; <<>> DiG 9.10.6-P1 <<>> ns com.
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 24500
;; flags: qr rd ra ad; QUERY: 1, ANSWER: 13, AUTHORITY: 0, ADDITIONAL: 1
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 512
;; QUESTION SECTION:
;com. IN NS
;; ANSWER SECTION:
com. 68524 IN NS l.gtld-servers.net.
com. 68524 IN NS c.gtld-servers.net.
com. 68524 IN NS d.gtld-servers.net.
com. 68524 IN NS f.gtld-servers.net.
com. 68524 IN NS b.gtld-servers.net.
com. 68524 IN NS h.gtld-servers.net.
com. 68524 IN NS m.gtld-servers.net.
com. 68524 IN NS j.gtld-servers.net.
com. 68524 IN NS k.gtld-servers.net.
com. 68524 IN NS i.gtld-servers.net.
com. 68524 IN NS g.gtld-servers.net.
com. 68524 IN NS a.gtld-servers.net.
com. 68524 IN NS e.gtld-servers.net.
;; Query time: 21 msec
;; SERVER: 8.8.8.8#53(8.8.8.8)
;; WHEN: Tue Jan 08 21:13:06 GMT Standard Time 2019
;; MSG SIZE rcvd: 256
This gives us a list of the name servers looking after the .com domain. So we query one of these to find the Glue records for google.com.
C:\Users\timdu>dig +norecurse ns @a.gtld-servers.net google.com
; <<>> DiG 9.10.6-P1 <<>> +norecurse ns @a.gtld-servers.net google.com
; (1 server found)
;; global options: +cmd
;; Got answer:
;; ->>HEADER<<- opcode: QUERY, status: NOERROR, id: 23933
;; flags: qr; QUERY: 1, ANSWER: 0, AUTHORITY: 4, ADDITIONAL: 9
;; OPT PSEUDOSECTION:
; EDNS: version: 0, flags:; udp: 4096
;; QUESTION SECTION:
;google.com. IN NS
;; AUTHORITY SECTION:
google.com. 172800 IN NS ns2.google.com.
google.com. 172800 IN NS ns1.google.com.
google.com. 172800 IN NS ns3.google.com.
google.com. 172800 IN NS ns4.google.com.
;; ADDITIONAL SECTION:
ns2.google.com. 172800 IN AAAA 2001:4860:4802:34::a
ns2.google.com. 172800 IN A 216.239.34.10
ns1.google.com. 172800 IN AAAA 2001:4860:4802:32::a
ns1.google.com. 172800 IN A 216.239.32.10
ns3.google.com. 172800 IN AAAA 2001:4860:4802:36::a
ns3.google.com. 172800 IN A 216.239.36.10
ns4.google.com. 172800 IN AAAA 2001:4860:4802:38::a
ns4.google.com. 172800 IN A 216.239.38.10
;; Query time: 24 msec
;; SERVER: 192.5.6.30#53(192.5.6.30)
;; WHEN: Tue Jan 08 21:15:32 GMT Standard Time 2019
;; MSG SIZE rcvd: 287
Because we’re querying the TLD’s nameservers directly we’ll always get the current glue records for the domain as opposed to a cached version.
You can apply the above principles to find the current glue records for any domain on the web including your own.