What if I link a_very_famous_brand.com to my IP server as an a A record?

Question

I discover how the whole A and CNAME records work and I'm a bit confused because my registrar let me enter watever I want into the field 'Name', next to my ip. So, saying I'm entering 'a_famous_brand.com', it seems I just have to wait 3 hours before the entire world think that my IP is.. 'a_famous_brand.com'

I suppose I have misunderstood something...?

Answer 1

Doesn't work that way.

If you enter a_famous_brand.com as your domain name, you are still not the registrant of that domain and according to the DNS information that info will not be fetched from your dns settings, it will be set from the settings of the registrant. That will be just a waste of time having no impact on any dns values.

Some useful explanation found here

The name server doesn’t know the IP address for www.abc.com, so it will start the following chain of queries before it can report back the IP address to your computer (the numbers below correspond to the numbers in the image).

1.Query the Internet root servers to get the name servers for the .com TLD.

2.Query the .com TLD name servers to get the authoritative name servers for abc.com.

3.Query the authoritative name servers for abc.com to finally get the IP address for the host www.abc.com, then return that IP address to your computer.

4.Done! Now that your computer has the IP address for www.abc.com, it can access that host.

Useful Resource 1

Useful Resource 2

Useful Resource 3 [Credit @Johannes H.]

Answer 2

You can do that. It won't harm anybody, because your name servers are not the ones listed in the TLDs (.com in your example) nameservers records, so they are not authoritative.