I am trying to set up a configuration using an ASA 5510 ( V 8.2(1) ) in routing mode to
- act as an IGMP stub in one way
- transparently forward multicast stream in the other way
I used 2 commands (the "multicast-routing" is enabled)
- igmp forward interface (for the IGMP proxy)
- igmp static-group (to forward defined multicast streams) (by the way, it's a shame I cannot use the " igmp static-group * " command like on a C3750)
The following schematic will help you understand:
On my LAN, the user is subscribing to the remote Cam 2 multicast stream (126.96.36.199). And on the same LAN, the Cam 1 is sending multicast stream (188.8.131.52) that has to be transparently forwarded to the WAN for distant subscribers.
BUT, the thing is that I cannot use both commands at the same time. In this configuration, the ASA is blocking the Cam 1 stream. Only the incoming stream is forwarded to the LAN. If I disable the IGMP stub function, the Cam 1 stream is going through the firewall! It seems that the first command is suppressing the second command.
So I've found a solution (not THE solution): I use a double physical interface to the WAN from the ASA:
But this is a very "strange" solution...
So do you know why the two commands seems to be incompatible?
(I have one constraint: I cannot enable the PIM protocol on the ASA, It MUST transparently)