We are currently setting ourselves up as an ISP and need to setup our own DNS servers for hosting multiple domains. Once we have setup our DNS servers does anyone know if we need to register these anywhere to allow us to host our clients domains or is this just a question of transferring the domain to our servers?
Thanks in advance.
Good starting points for understanding DNS are DNS and BIND and WP: Domain Name System.
No you don't have to register anywhere.
All you need to do is to have the owner of the domain to set your DNS servers as the responsible servers for the DNS zone.
For reverse resource records, that's another story.
For your IP blocks you have to set the delegations to the zones in your Internet Registry database. (the exact process depends on who is your Internet Registry).
You do not need to register your name servers anywhere, at least not in the regard that there is a master list of name servers or a club you must join.
When your name servers are authoritative it is simply a question of using your own name servers when you register/update the domain names for your clients. The registrar will include the required relevant glue record for your nameservers in the relevant TLD root-zone as part of the registration.
It was considered good practice to register all your clients domains using your own name server records, i.e. always use ns1.ispname and ns2.ispname, rather than unique name servers for each client domain you register (i.e. don't use ns1.client-domain & ns2.client-domain for each unique client-domain you register).
Ensure that your authoritative name server does not allow recursion.
If you want to provide name servers as part of your infrastructure, in the form of caching name servers that do allow recursion, you simply provide their ip-addresses to your customers and that's it. It is considered good practice that your caching servers are restricted to your own ip-ranges so only your own customers can use them.
