Re: Fw: [NTBUGTRAQ] Win 2003 DNS requests makes replies over 512 byte PIX limit

["hggdh" <hggdh () attbi com>]

I am sorry I did not explain myself here -- my fault. Apologies to Mathias,
Peter, and Ron.

Indeed almost all name server in use will use TCP for larger replies. They
probably did not get any responses because, as a lot of people out there,
they only allow UDP for DNS.

But Windows 2003 implements EDNS0 (RFC2671), which allows for UDP payloads
larger than 512 bytes...

The actual point/thing I am curious about is on the WIndows 2003 DNS
behaviour (I cannot test it right now) -- why would it start requesting a
truckload of info (as compared to WIndows 2000 DNS)?

In fact, WHAT is it it is requesting?

I plan on setting a 2003 test box as a name server, and I will look at it;
but, with people jumping in W2003, and using it as their name server, this
might become a hurdle.

Cheers,

..hggdh..


----- Original Message ----- 
From: "Mathias Gerber" <mathias () intergga ch>
To: <full-disclosure () lists netsys com>
Sent: Thursday, May 08, 2003 15:36
Subject: Re: [Full-disclosure] Fw: [NTBUGTRAQ] Win 2003 DNS requests makes
replies over 512 byte PIX limit


> Hello hggdh,
> On Thu, 8 May 2003 12:09:22 -0500 you wrote:
> > FYI. Any ideas?
> > > We are running the latest version (6.3.1) on our Cisco PIX and it
> > > appears that there is hard limit of 512 bytes on ANY UDP packets
> > > arriving on port 53.  Everything exceeding that is dropped.
> AFAIK the DNS uses TCP for larger replys.
> -- 
> mathias
> _______________________________________________
> Full-Disclosure - We believe in it.
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