CNAME record

What it means

A CNAME (canonical name) record says that one DNS name is an alias for another DNS name. It does not contain an IP address and does not redirect a browser to a different URL. When looking up an address through an alias, DNS resolution continues toward the target's relevant records. The web request still needs a server configured for the hostname the user visited. CNAME processing CNAME clarification

Try it

Simulation — trace an alias graph, then break one rule. Inspect the fixed records and choose Trace selected graph. A successful trace reaches the target's address; a conflict, loop, missing target or educational depth limit produces a stop instead of an invented address.

Compare the direct alias with the two-alias graph. Both reach the same address through different paths. Then choose CNAME plus ordinary TXT at the same owner, or an apex CNAME alongside SOA/NS. These fixtures deliberately violate ordinary-data coexistence rules. Removing a timeout or extending a trace cannot resolve that conflict. CNAME consistency Alias clarification

The target being absent from this small map is not a live finding about a domain. DNSSEC-related metadata exceptions, caching each link and provider flattening are outside the scene. Reset returns to the untraced direct alias. A DNS alias does not itself send an HTTP redirect or change the hostname a certificate must cover.

Coexistence and the zone apex

At a standard CNAME owner name, the alias cannot coexist with ordinary resource records such as A, AAAA, MX or TXT. DNSSEC-related records have narrowly defined exceptions; that is not general permission to mix a CNAME with ordinary data. The apex of a zone needs SOA and NS records, so a standard CNAME at that same apex conflicts with those requirements. CNAME rule Zone records

Some providers synthesize A/AAAA responses from a target name at the apex; read their provider documentation rather than assuming this is standard CNAME behavior. DNS also has standardized SVCB/HTTPS AliasMode for certain services, which is not equivalent to a generic CNAME and has different client support. Service binding AliasMode

In practice

Before editing an alias, record the exact owner name and target, check whether any ordinary records already exist at that owner, and use the hosting provider's documented configuration. Never replace a zone apex's NS/SOA or its MX/TXT mail data with an arbitrary CNAME. A CNAME doesn't itself provide a TLS certificate or move site contents.

Compare A and AAAA records for literal addresses. For a controlled cutover use Change a DNS record safely.

Key takeaways

Use CNAME for a name-to-name alias, not an IP value or an HTTP redirect. Check the owner for ordinary-data conflicts and the target chain for a usable endpoint. Apex alternatives and provider-specific features need their own documented rules; they are not permission to create an ordinary conflicting CNAME.