trouble with .gov dns?

Mon May 2 17:13:11 UTC 2011

* 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.

This has been noted before, for example:

From: Mark Andrews <marka at isc.org>
Subject: [dnsext] Failure to add glue MUST cause TC to be set.
To: dnsext at ietf.org
Date: Sun, 20 Feb 2011 08:07:15 +1100
Message-Id: <20110219210716.72943A5602B at drugs.dv.isc.org>