On Mon, 14 Mar 2022 at 22:55, BD dzidek23@gmail.com wrote:
I think you are right in principal. The only issue is there's more than just two levels of DNS (the router and google). Have a look at https://en.wikipedia.org/wiki/Domain_Name_System
Indeed, I know I simplified it.
But as I understand it it's multiple levels of the same: the authoritative DNS server knows the answer, and it isn't pushed anywhere from them, but pulled on request by a client (and then cached in multiple places which may or may not follow TTL).
Therefore if at any point the authoritative DNS is wrong (missing records, wrong records), and a request is made from it, there is a delay in any correction propagating due to those caches. However - and this is the crucial bit - if no requests are made while it is wrong, then no incorrect information ever makes it into those caches, so there is no correction to propagate.
To give a simple example: If you put a wrong entry into your DNS, access it using your web browser, realise your mistake, then correct the DNS, it will take some time before you'll be able to refresh your browser to see the correct result. However, if you discover the mistake and correct it before you access it (and before anyone else accesses it), the web browser will access it correctly on first attempt - there isn't a delay replacing the wrong information with the right information provided the wrong information was never accessed.
(Again: this is all as I understand it, what I am being told would make the above wrong. But it is both my understanding and my experience which I describe above so I'm having a hard time believing it is wrong without someone more authoritative on the subject than me telling me otherwise, and I can't automatically assume the person in a chat support session from a web hosting company is correct, nor am I arrogant enough to assume they are not.)