Re: kern/52554: IPv6 connections not routing to default gateway

[Roy Bixler <rcbixler%nyx.net@localhost>]

On Fri, Sep 29, 2017 at 07:56:13AM -0600, Roy Bixler wrote:
> On Thu, Sep 28, 2017 at 09:55:01PM +0000, Ryota Ozaki wrote:
> >  Oh sorry, I suppose to see packets of telnet by tcpdump on br0 and eth0
> >  of Linux. I suspected that a SYN packet is broken and filtered out on the
> >  interfaces for some reasons. And also we may see a SYNACK packet on
> >  the interfaces if a SYN packet reaches the server.
> 
> I wasn't thinking the same way, since I have had success with IPv6 on
> guests running different operating systems, like NetBSD 7.1.  I also
> have success with IPv6 on NetBSD 8 when connecting to other hosts on
> the same LAN.  That only changes when I try to connect outside the
> LAN.
> 
> I decided to try something different, which is an "ssh" connection
> with IPv6 to a host outside of the LAN.  I run tcpdump locally and on
> the remote host.  What appears to happen is that the NetBSD 8 host
> sends its SYN packets, the remote host receives them and tries to
> reply, but NetBSD 8 never sees the replies.

Because of this, I started to wonder if there's just some coincidence
at play here and NetBSD 8 somehow grabs a bad router when it does its
DHCP negotiation.  I have a working NetBSD 7.1. setup which has a
different IPv6 router so, after booting up the NetBSD 8 system, I
manually changed the default router to match the NetBSD 7.1 system.
Then I started getting replies to my IPv6 connections outside the
LAN.  So, the problem appears to be a purely a local one. :/

-- 
Roy Bixler <rcbixler%nyx.net@localhost>
"The fundamental principle of science, the definition almost, is this: the
sole test of the validity of any idea is experiment."
-- Richard P. Feynman