Dynamic DNS updates are attempts to update the PTR record, which is often done in conjunction with HOST A record update.
In order to send a PTR update an SOA query is made first for the reverse record for the host to see who is authoritative to accept the update.
DNS also provides a reverse lookup process, in which clients use a known IP address during a name query and look up a computer name based on its address.
A reverse lookup takes the form of a question, such as "Can you tell me the DNS name of the computer that uses the IP address 192.168.1.20?
This type of query expects an IP address as the resource data for the answered response.
When initially installing and configuring Windows DNS server, one of the first tasks to perform is the creation of forward lookup zones (and possibly reverse lookup zones).
In plain speak, this is when the domains that will be served by this DNS server will be configured.
The following sections describe tests that you can perform to verify that your DNS server is working properly, that the forward and reverse lookup zones are properly configured, and that DNS can support Active Directory.
If you use either the Configure DNS Server wizard or the Active Directory Installation wizard to install your Windows 2000 DNS server, most configuration tasks are performed automatically and you can avoid many common configuration errors, but you might still want to perform the tests in this section.