Re: [mpls-linux-general] ipip and mpls

[S. <j....@gm...>]

"James R. Leu" schrieb:

> <...>

>
> Depending on the order of things the route cache maybe interfering.
>
> Specifically the old route cache entry (using normal routing) may still=
 be
> in use.  One thing to try to eliminate this, is to let the route cache
> expire, or reboot router 2, then re-setup the MPLS tunnel, making sure =
not
> to send traffic from router1 to router3 before the MPLS tunnel is setup.
> I will look thourgh the code this weekend to see if there if I am some =
how not
> flushing the route cache at the right time.
>
> Another thing to look for is RPF or spoof filters.  Debian and a couple=
 of
> distributions put these in place, and hamper the use of MPLS tunnels (b=
ecause
> they are by there nature uni-directional and are a-symetric, this
> is exactly what RPF and spoof filters try to prevent :-).
>
> One last thing to help us help you :-) is turn on MPLS debugging (mplsa=
dm -d)
> and run a couple of pings, then turn it off (mplsadm -d again) and look=
 at the
> kernel log (dmesg).  If the MPLS code is being triggered you'll see gob=
s of
> debug messages, if the IP stack is the culprit you won't see any debug
> messages.
>
> I hope this helps,
> Jim
>

ok, I might find the problem ... even if it is a bit strange:
I have to build up ipip-tunnels bidirectional, what means, router2 in my =
example
needs to be configured with a tunneldevice, too. (Thanks for the idea)
It's really difficult to find appropriate information about ipip-tunnelin=
g in the
web, so I have to find out on my own.

Greetings - J=F6rn