bind v8.2.4 and win2k dns ixfr interop problem

[Everett Kropf]

No, the w2k box is setting the AA bit for ordinary queries. It even sets AA for AXFR's. Watching the different transfer types through named-xfer in a debugger shows that an AXFR zone transfer passes this code in named-xfer.c:
        if (hp->rcode != NOERROR || !hp->aa || qdcount != 1 ||
            (ancount < 1 && aucount < 1)) ...
but an IXFR zone transfer will not. Looking at the aa member of the HEADER structure shows that the aa bit is set for AXFR's from the w2k server, but not for IXFR's.

Mark.Andrews at nominum.com wrote:
> 
>         My bet is that the W2K box is not setting AA for ordinary
>         queries in this zone also.  Examine the event log.
> 
>         Mark
> 
> >
> > The setup:
> > A win2000 dns server is acting as master (host win1).
> > A HP-UX 10.20 machine running bind v8.2.4 as a slave (host hp1).
> >
> > win1 serves as primary master for the zone with dhcp services running
> > sending dynamic updates to the zone. hp1 is a slave server (who is
> > also authoritative for the zone) that gets notices from win1 to update
> > the zone. hp1 will try to use IXFR to transfer the zone, but logs the
> > error:
> >
> > Jun 13 09:30:18 hp1 named-xfer[7571]: [172.18.188.20] not
> > authoritative for learjet.com, SOA query got rcode 0, aa 0, ancount
> > 15, aucount 0
> > (172.18.188.20 is win1)
> >
> > After careful digging (let me know if you want all the steps I took to
> > trace this down), I found that the MS dns server is not setting the aa
> > flag in it's IXFR query responses.
> >
> > I've only found two ways to make these machines play together. The
> > first is to make the unix machine the master (the suits won't take
> > this solution; the Windows machine just HAS to be the primary). The
> > other method is to modify named-xfer to ignore whether or not the aa
> > bit is set (I definately do not like this solution).
> >
<snip>

-- 
Everett Kropf <everett.kropf at learjet.com>
IT Unix Group, Learjet, Bombardier Aerospace

Confidence is the feeling you have before
you understand the situation.