Strange IPv6 in FreeBSD 9.1RC1

[Zach Leslie]

HI Folks,

I've got two boxes that I recently moved from -stable to 9.1rc1.  I did
them one at a time, with about a week between the upgrades.  After the
first upgrade, I noticed something strange with networking but didn't
really dig into it much.  After the second upgrade immediately experiencing
the same issues, I figured it seemed to be something related to 9.1rc1.

What I am finding is that packets that originate from the FreeBSD boxes do
not get returned when running IPv6.  V4 seems to be fine.  I can also shell
into the boxes without issue, which is strange, since I would figure if
there were network issues, then I would see it for both in and out.  So box
sends a syn outbound, ack is never returned.  I can see on the destination
boxes interface   that the return packet is never actually generated.
 Running tcpdump -nei pflog0 doesn't show any blocked return packets, so I
think the packets are just not getting generated.  I don't really
understand how this could be honestly.

I first thought it was an issue with a Linux box, since its running a
service that both boxes are trying to talk to, but I don't think this is
the case.  I see the same behavior when I try to shell from one FreeBSD box
to the other.

I was encouraged to send a note to the list, even though I have very little
concrete.  Is anyone else seeing any strange IPv6 related networking issues
on 9.1RC1?


-- 
Zach