Re: IPv6 multicast forwarding

[Pekka Savola]

On Fri, 24 Oct 2008, Alejandro Riveira FernÃndez wrote:
> > Let me apologize in advance for the length of this message - it is long!
> >
> > I'm trying to test out IPv6 multicast forwarding on a 2.6.26 kernel
> > and I'm getting some strange values for the upcall messages from the
> > kernel. My code is below, but to give an overview, my setup is as
> > follows:
> >
> >     sender ------ ff15::1 -----> [eth1] linux 2.6.26 [eth0] ------> ...

Maybe this isn't the bug you're looking for but you shouldn't be using 
ff1x multicast addresses in a test like this; ff1x means that the 
multicast group is of "interface-local scope" and it isn't useful for 
multicast forwarding.  So the kernel might be correct in not 
installing multicast forwarding state for a group address like this 
(but if it's a conscious decision, maybe the failure mode should be 
better).  See S 2.7 of RFC4291.

--
Pekka Savola                 "You each name yourselves king, yet the
Netcore Oy                    kingdom bleeds."
Systems. Networks. Security. -- George R.R. Martin: A Clash of Kings