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From: Paul Koene <paul@wcclan.net>
To: "freebsd-questions@freebsd.org" <freebsd-questions@freebsd.org>
Date: Sun, 19 Dec 2010 21:37:30 +0100
Thread-Topic: IPv6 Unkown header extension
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Subject: IPv6 Unkown header extension
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L.S.,

every once in a while I see the following messages filling the logs on my F=
reeBSD installations:
IPFW2: IPV6 - Unknown Extension Header(128), ext_hd=3D0

I am somewhat curious why this message occurs. Did I configure something wr=
ong, Is there an implementation defect in an existing ipv6 stack that these=
 packets try to abuse or is this part of an OS fingerprinting technique or =
something?

Kind regards,

Paul Koene=