ANAME

Dynamic domain root aliasing

ANAME records – alias the domain root to another host name

A common challenge faced by DNS administrators is being able to alias the root or apex of a zone to another hostname, much in the same way that you might do so with a named record.

The following example works: www.mydomain.tld CNAME to xyz.mydomain2.tld
However, this does not: mydomain.tld points CNAME to xyz.mydomain2.tld

RFC 1033 expressly requires the apex of a zone to be one or more A and/or AAAA records, which means that CNAMEs in their usual form cannot be used.

This has become more of a challenge in recent years as services such as Amazon EC2, Google App Engine and Microsoft Azure provide administrators with resolvable hostnames for machines that point to IP addresses that may change in the future. This means that the workaround of creating an A record instead is not a reliable option.

Conexim addresses this challenge providing the benefits you would expect from being able to have a CNAME on the zone apex or root of the domain while maintaining full RFC compliance.

This is achieved by creating a new custom record type called an ANAME record whereby administrators can specify the destination host name. Conexim’s global AnyCast DNS servers then internalise the resolution of the destination A and AAAA records and present them as valid A/AAAA records on the zone.

The end result is transparent and compliant – enjoy!