ALIAS record
A non-standard DNS record type that behaves like a CNAME but is allowed at the apex. Implemented by several DNS providers under different names.
An ALIAS record is a DNS-provider-specific feature that lets you write example.com ALIAS target.cloud.com and have it work, despite the RFC saying CNAMEs at the apex are illegal.
It's the same idea as CNAME flattening: the DNS provider resolves the target server-side and returns A records to whoever asked, so the resolver never sees a CNAME at the apex.
Vendor naming
The exact name varies:
- DNSimple, Namecheap, easyDNS: "ALIAS"
- Cloudflare: "CNAME Flattening" (automatic for the apex)
- Route 53: "Alias" (only to specific AWS targets like ELB / CloudFront)
- DNS Made Easy: "ANAME"
- OVHcloud: "ALIAS"
Functionally they all do the same thing.
Why it's not standardized
There's no RFC for ALIAS. Each provider implements it differently. Records aren't transferable between providers via zone export, because the receiving provider may not have an equivalent record type.
If you ever migrate DNS providers, audit your apex records first.
When you need it
You need an ALIAS (or equivalent) whenever:
- Your customer wants to point their apex (
example.com) at a hostname (edge.someapp.com), AND - Their DNS provider supports it.
If their DNS provider doesn't support ALIAS, two options remain: instruct them to use www.example.com via CNAME and 301-redirect the apex to www at their registrar, or have them switch DNS providers.