1. RFC 1035 (http://www.ietf.org/rfc/rfc1035.txt), section 3.2.2,
mentions AXFR requests and * requests. Are AXFR requests always
supersets of * requests? Based on the queries I've captured with
Wireshark, it seems like they might very well be.

2. according to <http://cr.yp.to/djbdns/axfr-notes.html>, "each packet
[in an AXFR response is] preceded by a 2-byte length". Also, "several
DNS packets can be combined into one TCP packet". My question is...
how do you know when you've reached the end? In HTTP/1.1 chunking
(which sounds pretty similar to this), you keep on reading x bytes,
after x is defined, until at some point, x is zero. DNS responses,
however, don't appear to do this. atleast that's the conclusion I'm
drawing from my Wireshark captures. so my original question remains -
how do you know when you've reached the end?

In article <1175217100.358876.166500@b75g2000hsg.googlegroups .com>,
"yawnmoth" <terra1024@yahoo.com> wrote:

> 1. RFC 1035 (http://www.ietf.org/rfc/rfc1035.txt), section 3.2.2,
> mentions AXFR requests and * requests. Are AXFR requests always
> supersets of * requests? Based on the queries I've captured with
> Wireshark, it seems like they might very well be.

I guess you could look at it like that. * asks for all the records of
one name, AXFR asks for all the records of all names in the zone.

>
> 2. according to <http://cr.yp.to/djbdns/axfr-notes.html>, "each packet
> [in an AXFR response is] preceded by a 2-byte length". Also, "several
> DNS packets can be combined into one TCP packet". My question is...
> how do you know when you've reached the end? In HTTP/1.1 chunking
> (which sounds pretty similar to this), you keep on reading x bytes,
> after x is defined, until at some point, x is zero. DNS responses,
> however, don't appear to do this. atleast that's the conclusion I'm
> drawing from my Wireshark captures. so my original question remains -
> how do you know when you've reached the end?

This is answered in the first paragraph of the section titled Zone
Contents:

A zone is a series of DNS records, starting with an SOA record for the
requested name, continuing with any number of non-SOA records, and
concluding with a repetition of exactly the same SOA record. (RFC 1034,
which says that all of the records for the zone name are repeated, is
wrong.) The zone data is complete when the SOA record appears again.

--
Barry Margolin, barmar@alum.mit.edu
Arlington, MA
*** PLEASE post questions in newsgroups, not directly to me ***
*** PLEASE don't copy me on replies, I'll read them in the group ***

On Mar 30, 12:02 am, Barry Margolin <bar...@alum.mit.edu> wrote:
> <snip>
> This is answered in the first paragraph of the section titled Zone
> Contents:
>
> A zone is a series of DNS records, starting with an SOA record for the
> requested name, continuing with any number of non-SOA records, and
> concluding with a repetition of exactly the same SOA record. (RFC 1034,
> which says that all of the records for the zone name are repeated, is
> wrong.) The zone data is complete when the SOA record appears again.
I guess I didn't get that far in my reading - thanks!