Because the domain name and DNS subtree it refers to can belong to different zones, the DNAME record must always be entered as a fully qualified domain name. NameSurfer checks that the subtree really is an existing domain name, and issues a warning if the name does not exist.

DNAME records are useful in conjunction with IPv6 A6 resource record and binary labels. It is supposed that all the delegations made for IPv6 reverse maps are made using DNAMEs. For example if ISP A.NET delegates part of its reverse map to the client X.EXAMPLE it does it like \[x11/8].IP6.A.NET DNAME IP6.X.EXAMPLE. The DNS protocol places a number of restrictions on the use of DNAME records:

• A name with a DNAME record may have other records (but CNAME or other DNAME).
• There should be no other records in the same zone which are name descendants.
• Other records that "point" to domain names, such as NS, CNAME A6 and PTR.