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Re: trouble with .gov dns?


From: Florian Weimer <fw () deneb enyo de>
Date: Mon, 02 May 2011 19:31:07 +0200

* William Herrin:

On Mon, May 2, 2011 at 1:13 PM, Florian Weimer <fw () deneb enyo de> wrote:
* William Herrin:
Anyone else having trouble with .gov DNS failing with edns-udp-size
set to 512?

You need an UDP size of at least 1220 for DNSSEC, see RFC 3226,
section 3.  A query that advertises a smaller buffer size is
non-compliant.  BIND will send such queries, but this is a
controversial feature.

I have "dnssec-enable no;" in my bind config.

It does not seem to have the intended effect.

Were you able to determine from the tcpdump output that DNSSEC was
being requested?

[udp sum ok] 10320 [1au] A? www.nsf.gov. ar: . OPT UDPsize=512 OK (40)
11:53:01.690414 IP (tos 0x0, ttl 249, id 28744, offset 0, flags

"OK" means that DO=1 was set.


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