On Thu, Oct 29, 2009 at 05:04:02PM -0500, Neulinger, Nathan wrote:

Now I see it - Stephen actually had it right on - the problem is that
the gre tunnel is creating a MAC address on the fly based on the tunnel
endpoint ip address, so if the tunnel endpoint address starts with an
odd number, it hits the multicast check in the bridging code. (I'm sure
that's what he meant and I just missed it entirely.)

Simplest option would probably be to just mask off the first octet with
0xFD or using the ip as the last four octets of the mac instead of the
first four.

This looks like a bug in either iproute or the kernel.  It's
not supposed to set a MAC address unless the user specifically
gives one.  If one is not given the kernel will generate a valid
MAC address.

Cheers,
-- 
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