DNS on Windows Server 2003, 3rd Edition

8. Missing Subdomain Delegation

Even though registrars do their best to process requests as quickly as possible, it may take some time for your subdomain’s delegation to appear in the parent zone’s name servers. If your parent zone isn’t one of the generic top-level domains, your mileage may vary. Some parents are quick and responsive; others are slow and inconsistent. Just like in real life, though, you’re stuck with them.

Until your delegation data appears in your parent zone’s name servers, your name servers can look up data in the Internet domain namespace, but no one else on the Internet (outside of your domain) will know how to look up data in your namespace.

That means that even though you can send mail outside of your domain, the recipients won’t be able to reply to it. Furthermore, no one can telnet to, ftp to, or even ping your hosts by name.

Remember that this applies equally to any in-addr.arpa subdomains you may run. Until the parent delegates those subdomains to your servers, name servers on the Internet won’t be able to reverse-map addresses on your networks.

To determine whether or not your zone’s delegation has made it into your parent zone’s name servers, query a parent name server for the NS records for your zone. If the parent name server has the data, any name server on the Internet can find it:

 C:\> nslookup  
Default Server:  terminator.movie.edu 
Address:  192.249.249.3 

> server arrowroot.arin.net.       
               Query a 192.in-addr.arpa name server. Default Server: arrowroot.arin.net ...