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I have someone telling me that DNS servers only start responding after the whois record is updated to point at their DNS servers. Is this normal behaviour? Or should a DNS server respond before the whois record is updated?

Also, once the domain is active, (so either after the domain is added or after the whois record is update, depending on the answer to the above question) how long till the name servers should start responding?

I'm not referring to the time that it takes to propagate acorss the internet, but just the time on the name server for the domain. I am also not concerned with when the rest of the internet sees the change, only wondering when that DNS server should respond when using a command such as:

 nslookup www.example.com ns1.dnsserver.com
+2  A: 

DNS Servers operate completely separate from the Whois server. The relation of how fast DNS is updated after Whois depends completely on the registrar. A registrar or web host may update DNS within a second or 2 of a customer making a change in the control panel, or it may take minutes or hours if they make updates in batch mode.

Ideally all DNS changes that a customer request should happen very quickly on the DNS server (within a few seconds), but as you note, there may be a delay until changes propagate across the internet.

+2  A: 

For the DNS servers to be found what you call the whois record must know where to find them.
Stricly speaking, the whois record contains much more than just the DNS servers for a domain, but let's not nitpick.

Say your DesktopA needs to connect to example.com, the following servers will be contacted, assuming the answer wasn't already cached by your ISP's DNS or the local machine.

  • DesktopA has DNS settings pointing to the ISP, so DektopA will ask the ISP's DNS servers if they know where example.com. is located (its IP).

  • ISP DNS server doesn't know, so it will contact the root domain database for com. (all Fully Qualified Domain Names end in a ., even though we generally don't use it explicitly, but you can try insert it in web requests, it should work fine).
    This bootstrap list of global root servers is usually updated by the OS regularly.
    The root servers will know which Top Level Domain TLD server to contact for each global domain such as .com, .org, .uk, etc.
    In our example, the ISP will ask the root which server to query for com domains.
    The root server answers with the IP address of one of the the .COM TLD servers.

  • The ISP DNS server will now contact the .COM TLD server and ask it where to find EXAMPLE.
    The .COM database record for example.com will contain the 2 (or more) DNS servers registered along with the domain name example.com. These are part of your whois record.

  • The ISP now has the IP addresses of the DNS servers for example.com as setup in the whois. It will query the first one (or the second one if the first isn't available) and ask it: what's the IP of 'example.com'?

  • The DNS server for example.com will look in its records and return the A record defined for the example.com domain as IP 1.2.3.4 for instance.

  • Your ISP's DNS server will cache this information for a predetermined amount of time (TTL) and return the IP 1.2.3.4 to DesktopA.

  • Desktop A can now contact the server for example.com directly by its IP.
    DesktopA may cache this information for a little while for fast lookup.

Tis would be the same for subdomains such as www.example.com or john.people.example.com. Everything before the domain example.com must be declared in your DNS server so when someone query for their address, your DNS server for example.com can look up the definitions and answer them (it could very well pass them on to another server as well if necessary).

In conclusion

So, to go back to your question, your whois record must be set with the proper DNS records for your domain before anyone can access them using that domain name.

Renaud Bompuis
Yup, cool on this, but what about when the name server will start responding when a new domain is added to it, not matter what the whois record says?
Darryl Hein
It depends. They can respond immediately but some services will actually wait for the DNS record to be updated in the whois database.
Renaud Bompuis
The thing though is that if you add a domain to your name servers but these domains are not defined as being authoritative for the domain name (not in the whois), then no-one can find them.
Renaud Bompuis
I see you clarified your question.If you force the DNS questy to use a particular DNS server, then the DNS server should be able to answer straight away, but you need to check with the particular service you're using as some providers don't switch it on before the domain records are updated.
Renaud Bompuis