Let's asume, that I own the domain "example.com" and I should configure an internal subnet for my company.
I read, that when you want to install Active Directory, DNS and DHCP in an internal network you shouldn't use a TLD like .local, .intra or .lan, because with gTLD there could be a collision with already registered TLDs.
So the best pratice would be to create a subdomain, like "intra.example.com" for internal purpose only.
But when I create a subdomain on a Windows Server, this subdomain is accessable from outside. So what can I do, that this subdomain is only accessable from inside the network.
Alternatively, I also read that the following TLDs are reserved:
.test
.example
.invalid
.localhost
Would it be a proper setup, to have a domain like "company.com" for external purpose and a domain like "company.localhost" for internal purpose?
Thank you in advance.