[Pdns-users] Ignoring wildcard due to TXT record

Marten Lehmann lehmann at cnm.de
Thu Dec 13 12:17:14 UTC 2012


the odd thing is:

when we have a wildcard for the TXT record as well, subdomains are 
resolved correctly:

*.domain.com TXT "some text"
*.domain.com A

This returns for sub.domain.com for type A and "some text" for TXT.

> http://www.ietf.org/rfc/rfc1034.txt - 4.3.2, step 3.c spells out what we
> have to do.

To me this looks inconsistent. Wildcards are virtually useless if the 
resolver is that broken, even if a RFC from 1987 might describe it that way.

Besides that, the RFC does not go into record types at this point. It 
leaves it totally open to the implementation if step 3.c is tied to the 
requested record type or all records. If I query for an A record of 
sub.domain.com, then the resolver doesn't find "the corresponding label" 
for type A so it should look for a wildcard of type A then. It would 
find it in my case, so everything would be fine. What PowerDNS does 
instead is to stop, even if "the corresponding label" is only for a 
different type (TXT in this case).

This is badly wrong in my opinion. While both ways to implement it 
conform to the RFC, only the first way (looking for specific type) is 
the behaviour one would expect.

Is it possible to change the behaviour somehow? We really can't go into 
thousands of domains that rely on the 2.9 behaviour which now would be 
required to add additional A records.

Kind regards

More information about the Pdns-users mailing list