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I want to understand the process of how your domain gets queried from dns servers after purchasing a domain. I have not yet tried hosting and have no plans atm but I am eager to learn.
Here is what I have deduced so far (some are still speculations as I could not find the exact details of how it works). First, after purchasing a domain from the registrar, you will configure the DNS servers that will be authoritative for your domain in the registrar's DB. I speculate that aside from the names of the dns servers you will also configure the IP addresses of your name servers so a dns lookup on the registrar's DNS servers can give the IP of your authoritative name servers. Also, a whois look up for your domain would return the name servers you have configured.
Now that people have a way to learn your nameservers ip address, they can query your own authoritative name servers for the ip address of your domains and sub domains.
I know it is much complicated than that, but what I want to clarify is how domain registration works and how TLD name servers KNOW who your name servers are so they can redirect requests for your domain to your name servers. At the moment I think that configuring your name servers in your registrar's db also configures the TLD name servers and the whois database. Is this correct? Or is there a separate process? I am confused whether or not the domain registrar also handles the TLD name servers.