DNS CNAME record conflicts with other types

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If you have a CNAME for a subdomain, this will block the other records for that same subdomain.

 subdomain.domain.tld TXT blaaaaaaablaaaaaaaaaaa
 subdomain.domain.dlt CNAME some.domain.other

A query for the TXT record will only return the CNAME as it short circuits the lookup - just like at the case for a bare domain CNAME record.

Reference:  https://www.rfc-editor.org/rfc/rfc1034

If a CNAME RR is present at a node, no other data should be
present; this ensures that the data for a canonical name and its aliases
cannot be different.  This rule also insures that a cached CNAME can be
used without checking with an authoritative server for other RR types.

But as always, in the case of "should" in an RFC, you might find odd behavior based on your implementation, but it would probably
be better if the semantics of handing off the queries to the alias domain remain intact.