DNAMEVALUE

DNAMEvalue refers to the data portion of a DNS DNAME resource record. It is the target domain name that the DNAME maps a subtree to, and it plays the central role in how the DNAME record redirects an entire set of names under its owner to another naming space. In a zone file, the DNAME record associates the owner name with a DNAME value, such as example.org., which means that every name under the owner subtree is aliased to the corresponding name under the target subtree.

Technically, the DNAME value is the domain name that serves as the destination for the entire subtree referenced by the DNAME owner. When a resolver queries a name within that subtree, the resolver rewrites the query by replacing the DNAME owner suffix with the DNAME value and then resolves the resulting name in the destination zone. The practical effect is that names like sub.domain.example can be redirected to sub.destination.example.org, without requiring individual records for each subname.

DNAME records are used to facilitate zone migrations, policy changes, or centralized aliasing of subdomains. They differ from CNAME records in scope: a DNAME affects an entire subtree, whereas a CNAME maps a single name to another name. DNAME is typically not placed at the zone apex because it adversely interacts with essential zone records (such as NS and SOA) and can complicate resolution if misconfigured. In practice, DNAMEvalue enables large-scale redirection while preserving the existing structure of the source zone.

See also: DNS, DNAME record, CNAME, DNS resolution.