question about multiple queries in a single dns packet

[Michael Sinatra]

On 12/29/10 14:06, Alan Clegg wrote:
> On 12/29/2010 2:17 PM, Federico Barbieri wrote:
>> Not sure if this is the right place to ask but I've been trying to dig
>> around and found nothing...
>>
>> reading the dns specification it would seems possible to send multiple
>> request in a single packet.
>
> I'm not sure what the actual reference is, but "don't do that".
>
> Nobody supports it (what would the answer section contain?  what does
> the RCODE actually mean?)...

I believe it's in the EDNS1 specification that Paul did a while back, 
after EDNS0.  I don't think it ever got advanced to RFC:

http://tools.ietf.org/html/draft-ietf-dnsext-edns1-03

See especially section 4.

The answer to your question on RCODE:


4.2. RCODE and AA apply to all RRs in the answer section having the

    QNAME that is shared by all questions in the question section.  AA
    applies to all matching answers, and will not be set unless the exact
    original request was processed by an authoritative server and the
    response forwarded in its entirety.

michael