Will a wildcard CNAME take precedence over a named CNAME record?

Question

Generally wondering whether its possible to have both a CNAME entry with a " * " to domain and a seperate subdomain mapping i.e. like

*              | CNAME | domain.com
bla.domain.com | CNAME | some.example.com

Is this possible or does the * overwrite the "bla.domain.com" and therefore when you enter "bla.domain.com" you go to "domain.com" ?

score 19 · Answer 1 · answered Feb 28 '10 at 20:04

19

In BIND, the wildcard matches when another record does not exist. See http://en.wikipedia.org/wiki/Wildcard_DNS_record.

answered Feb 28 '10 at 20:04

Warner

6

Not just BIND, any RFC 1912 DNS server will do this. – BrianEss Feb 28 '10 at 23:23
1

RFC1912 is telling _operators_ how not to do wildcards. RFC 1035 is the one that _servers_ comply with. – Alnitak Sep 16 '10 at 12:42

score 14 · Answer 2 · edited Oct 07 '21 at 06:47

14

A more specific entry always overrides a wildcard, not the other way around.

For chapter and verse, see §4.3.3 of RFC 1034.

edited Oct 07 '21 at 06:47

Community

answered Feb 28 '10 at 23:55

Alnitak

1

From the very last paragraph of section 4.3.3: "For example, if a wildcard RR has an owner name of \*.X, and the zone also contains RRs attached to B.X, the wildcards would apply to queries for name Z.X (presuming there is no explicit information for Z.X), but not to B.X, A.B.X, or X." – KajMagnus Jun 27 '12 at 05:19

2 Answers2