I have my setup working as expected (Vodafone router with public IP and internal IP, OpenWRT on static address on internal IP network and a second LAN)
I’m applying double NAT because Vodafone doesn’t provide a bridge mode nor static routing on their router. OpenWRT does masquerading to all the internal IPs. It is working, but the SetTop Box isn’t keen on this. The router is more than capable of keep up with the multicast video stream (it works fine on unicast streams below 10% cpu).
What I experience is that after a few seconds the stream breaks, then it resumes a few seconds later. Using TCP Dump it is clear that there is an issue with the multicast. Possibilly at layer 2 level as I have couple of unmanaged switches on the path between the router and the STB. The mac address used are "unknown" and not part of any hardware interface. As there is no reply, the switches may (this has happened to me on another project, on another setup) close off the connection or be unable to send the message back to the last L3 multicast node.
I've tried igmp snooping check on the interface UI, no luck. I've installed igmp proxy and udpxy, but I'm not sure (actually don't have clue!) how to configure it...
Help needed here! Thanks!