Subnet reverse delagation, RFC 2317

[Jukka Pakkanen]

29.7.2010 14:50, Phil Mayers kirjoitti:
> On 29/07/10 12:34, Jukka Pakkanen wrote:
>> 29.7.2010 14:23, Mark Andrews kirjoitti:
>>> In message<4C5134AF.2080302 at qnet.fi>, Jukka Pakkanen writes:
>>>
>>>> Doing first time the RFC 2317 style subnet reverse DNS, and have a
>>>> problem with recursion.  When doing a query like "dig @ns1.qnet.fi -x
>>>> 62.142.217.200" is succeeds from the local network, but outside I get
>>>> "recursion requested but not available".  Our /24 reverse zones work
>>>> fine, the server knows it's the master and serves ok, like "dig
>>>> @ns1.qnet.fi -x 62.142.220.5".
>>>>
>>> There is NOTHING wrong here.  You are not testing the servers properly.
>>>
>>
>> Uuh... NOW I'm confused :)
>>
>> There's definitely something wrong somewhere, because reverse-DNS for
>> 62.142.217.128/25 is not working as it should.
>>
>> ns1.qnet.fi should be the authoritive reverse DNS server for that IP
>> range, but it's not serving. Getting "recursion requested but not
>> available".
>
> No - Mark is right (apologies for my confusing posts). Assume an 
> example IP of 62.142.217.200. Your server is authoritative for:
>
> 200.128/25.217.142.62.in-addr.arpa.
>
> ...not:
>
> 200.217.142.62.in-addr.arpa.
>
> ns{3,5}.sci.fi have CNAMEs linking the two because they own the parent 
> zone, so can answer a "dig -x THEIP" directly.
>
> $ dig @ns3.sci.fi 200.217.142.62.in-addr.arpa ptr
>
> ;; QUESTION SECTION:
> ;200.217.142.62.in-addr.arpa.    IN    PTR
>
> ;; ANSWER SECTION:
> 200.217.142.62.in-addr.arpa. 14400 IN    CNAME 
> 200.128/25.217.142.62.in-addr.arpa.
> 200.128/25.217.142.62.in-addr.arpa. 86400 IN PTR x200.qnet.fi.
> _______________________________________________

Yeah, this makes sense.  But my question still is, what is wrong in our 
setup, since the goal is we can administer the 62.142.217.128/25 reverse 
DNS, without asking our upstream provider sci.fi for changes to the zone?

I also understand the requirement for the recursion, but I don't believe 
the cure is to allow recursion to "any" in the global options. I'm just 
browsing the net for zone specific recursion options, but haven't found 
anything yet...