[Pdns-users] pdns-recursor 3.7.4 on Redhat Linux always returns SERVFAIL for AAAA lookups

[Brian Candler]

On 16/08/2017 21:05, Kenneth Marshall wrote:
> Here is what dig says to the nameserver:
>
> dig -t AAAA file-open.rice.edu @open-ssip.rice.edu

dig +trace open-ssip.rice.edu aaaa

says there are 5 authoritative servers that rice.edu is delegated to:

rice.edu.        172800    IN    NS    ns1.rice.edu.
rice.edu.        172800    IN    NS    ns2.rice.edu.
rice.edu.        172800    IN    NS    ns3.purdue.edu.
rice.edu.        172800    IN    NS    ns4.purdue.edu.
rice.edu.        172800    IN    NS    dns.smu.rice.edu.

Asking one of those servers, it agrees:

$ dig +norec @ns1.rice.edu rice.edu. ns
...
;; ANSWER SECTION:
rice.edu.        3600    IN    NS    dns.smu.rice.edu.
rice.edu.        3600    IN    NS    ns3.purdue.edu.
rice.edu.        3600    IN    NS    ns4.purdue.edu.
rice.edu.        3600    IN    NS    ns2.rice.edu.
rice.edu.        3600    IN    NS    ns1.rice.edu.

So if open-ssip.rice.edu is authoritative, it's hidden. The recursor 
won't be sending anything to it, unless you've configured forward-zones 
or similar.  Have you?

As for the name "file-open.rice.edu", these servers say that it doesn't 
exist (neither A nor AAAA)

$ dig +norec @ns1.rice.edu. file-open.rice.edu. a
...
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 51751

$ dig +norec @ns1.rice.edu. file-open.rice.edu. aaaa
...
;; ->>HEADER<<- opcode: QUERY, status: NXDOMAIN, id: 40835

And actually, the name "open-ssip.rice.edu" doesn't exist either 
(NXDOMAIN ditto)