CNAME flattening
The apex should be allowed to point at a hostname.
RFC1034 forbids a CNAME at the zone apex beside other records. Teams still need example.com to follow a CDN or application target.
Cloud DNS supports CNAME flattening. The apex can alias a hostname while the authority returns A/AAAA answers resolvers expect.
Why teams use Aptranet
What CNAME flattening looks like on this network.
Cloud DNS answers on 210+ Anycast servers, with GeoDNS, health checks and a one-second minimum TTL for change.
Apex alias to a CDN hostname
Point the root at Cloud CDN or another target without a dedicated A record you have to chase.
Other apex records still work
MX, TXT and NS can coexist with a flattened alias.
Target changes without editing A records
When the alias target moves, flattening follows it.
How to set it up
A cutover you can validate before DNS moves.
Create the Cloud DNS configuration, prove it on an Aptranet hostname, then point production DNS when the path looks correct.
- 1Host the zone on Cloud DNS
Apex flattening is an authoritative-zone feature.
- 2Alias the apex to the target hostname
Usually the Cloud CDN or application hostname.
- 3Keep MX and verification TXT at the apex
Flattening is not a reason to drop mail or domain proofs.
- 4Validate from more than one resolver
Confirm A/AAAA answers and that mail records remain intact.
Outcomes
What changes once the hostname is on Aptranet.
- The apex can follow a hostname
- Mail and TXT records remain at the root
- CDN cutovers do not need a frozen A record
- Subdomain CNAMEs still work as usual
Keep reading
Related pages
More DNS use cases on the same Cloud DNS footprint.
Frequently Asked Questions
It solves the same apex-CNAME problem: the authority returns addresses for a hostname target.
Yes. Many sites use flattening so the apex and www both reach the distribution.
The answer TTL should follow operational policy, including the one-second minimum when you need it.
Cloud DNS supports HTTPS records as well. Use them where clients benefit, alongside flattening.