[Pdns-users] PowerDNS 2.9.21, CNAME wild cards, host(1) and AAAA lookups

[Jaco Engelbrecht]

Hi,

I've run into a possible bug/new feature/change of behavior with wild 
card records (which uses CNAME), host(1) and the latest version of 
PowerDNS authoritative server.

Essentially, PowerDNS version 2.9.21 returns the wild card record (which 
has been setup as a CNAME, see below) when asking for an AAAA records 
that do not exist.

Previous versions of PowerDNS, including Bind 9.4 with the same zone 
data, will only return the IPv4 record, and no wild card record.

PowerDNS 2.9.21:

bje at eris:~$ host host.test.internal
Using domain server:
Name: ns2.test.internal
Address: 172.20.194.28#53
Aliases:

host.test.internal has address 34.34.34.34 <- A record
host.test.internal is an alias for catch.test.internal. <- AAAA record
host.test.internal is an alias for catch.test.internal. <- MX record

The records in PowerDNS is as follows:

+--------------------------------+-------------------------------------------------------+
| name                        | content                    | record_type |
+--------------------------------+--------------------------------------------------------+
| *.test.internal         | catch.test.internal | CNAME         |
| host.test.internal   | 34.34.34.34             | A                    |
+--------------------------------+-------------------------------------------------------+

Bind 9.4.2 behaves the same as PowerDNS 2.9.20.

I can understand that this behavior is technically correct, and that if 
I do not want this to happen, I should change my record_type for my wild 
card from CNAME to A instead.  I'm just not sure if this is is intended 
behavior in the latest version of PowerDNS?  I can't see this mentioned 
in the change log?

Cheers,
Jaco

--

Behavior for host.test.internal against PowerDNS 2.9.20

bje at mana:~$ host -t AAAA host.test.internal
Using domain server:
Name: 172.20.32.2
Address: 172.20.32.2#53
Aliases:

host.test.internal has no AAAA record

bje at mana:~$ host -t A host.test.internal
Using domain server:
Name: 172.20.32.2#53
Address: 172.20.32.2#53
Aliases:

host.test.internal has address 34.34.34.34

--

Behavior for host.test.internal against PowerDNS 2.9.21

bje at mana:~$ host -t AAAA host.test.internal
Using domain server:
Name: 172.20.222.35
Address: 172.20.222.35#53
Aliases:

host.test.internal is an alias for catch.test.internal.

bje at mana:~$ host -t A host.test.internal
Using domain server:
Name: 172.20.222.35
Address: 172.20.222.35#53
Aliases:

host.test.internal has address 34.34.34.34