[LARTC] Multicast routing problem

[Raj Mathur]

Hi,

I'm trying to route multicast between 2 LANs using a GRE tunnel.  The 
setup is:

B to C is a GRE tunnel running over PPPoE.  B is the multicast router.

A is on the same LAN as B.  The same ethernet adapter is used for both 
the LAN and PPPoE connections.

I've setup smcroute since I only need static routing.  Multicasts sent 
from C (the remote machine) to B over the tunnel are properly routed by 
B and available over the LAN to A.  However, multicast packets 
generated by A (on the LAN), while received at B, are not routed to 
over the tunnel to C.  The multicast routes look fine, and I can see 
the input counters growing when I receive multicasts on the LAN.  
However tcpdump does not show any activity on the tunnel, the packets 
just seem to get dropped at B.

Kernel 2.6.16.  Any help appreciated.

Regards,

-- Raju
-- 
Raj Mathur            raju at kandalaya.org   http://kandalaya.org/
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