On Sun, Oct 06, 2013 at 02:06:12PM +0200, Steinar H. Gunderson wrote:

On Sat, Sep 28, 2013 at 10:33:18PM +0200, Hannes Frederic Sowa wrote:

quoted

quoted

So the “packet too big” packets really look like they're being ignored.
However, they _do_ reach the kernel somehow, since Icmp6InPktTooBigs
seems to increase.

Could this be related somehow to the packets coming from 2001:67c:29f4::31,
while the default route is to a link-local address? (An RPF issue?) This used
to work (although it was often flaky for me) in 3.10 and before. I can't
easily bisect, though, as I don't boot this machine too often.

This looks like a bug and should definitely get fixed. There should be
no RPF issue. May I have a look at your /proc/net/ipv6_route?

It started again, so now I could capture what you asked for:

Thanks!

Do you know which remote IP address is part in the failing communication? Same
as above?

Greetings,

  Hannes