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Date: Wed, 22 May 2013 11:39:05 -0400
From: Brian Hechinger <wonko@4amlunch.net>
To: freebsd-net@freebsd.org
Subject: GRE and BPF
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Hello all,

I've been having some trouble with a GRE tunnel. Specifically with
non-IP traffic (DECnet, in this case) and BPF.

I can see the GRE packets containing the DECnet packets coming over the
physical interface but when I do a tcpdump of bge0 I never see them.

This is an issue because the program I want to use will be using pcap to
pull packets off of the bge0 interface.

I can get IP packets off of the bge0 interface with tcpdump, however.

Is this just never going to work or am I missing something here?

The other end is a Cisco is it really matters.

I'm running:

FreeBSD wiggum 9.1-RELEASE FreeBSD 9.1-RELEASE #0 r243826: Tue Dec  4 06:55:39 UTC 2012 root@obrian.cse.buffalo.edu:/usr/obj/usr/src/sys/GENERIC  i386

Thanks!

-brian