I'm confused about the responses I'm getting doing a DNS query using authoritative vs non-authoritative and I'd appreciate you can help clarify.
When I query www.google.com using the authoritative server:
nslookup -debug www.google.com ns1.google.com
ANSWERS:
-> www.google.com
internet address = 172.217.195.147
ttl = 300 (5 mins)
When I query www.google.com using a non-authoritative server:
nslookup -debug www.google.com 8.8.8.8
ANSWERS:
-> www.google.com
internet address = 216.58.192.132
ttl = 235 (3 mins 55 secs)
As you can see the TTL of the authoritative server is the raw value of 300 but the TTL of the non-authoritative is the value showing how much time is left before it expires (it is counting down).
For the non-authoritative case, is the TTL really coming from the non-authoritative server or is that somehow showing the cache on my system?
If someone is using a non-authoritative server for as their DNS resolver, then does that mean they must honor what is returned so in the case where 1 is returned for TTL they must refresh again after 1 second ?