I'm trying to receive on my LInux box multicast frames from hosts on a different subnet. For the experiment, and ONLY for this experiment, i have two machines connected through a network switch:
- machine A (192.168.10.1/24) runs a simple application having a listening UDP socket (port 10000) joined on a multicast group (ex. 22.214.171.124);
- machine B (192.168.20.1/24) sends UDP datagrams (destination port 10000) to multicast group 126.96.36.199.
tcpdump on machine A I see packets sent by machine B but packets are not delivered to the application layer. The packets are delivered to the application layer only if machine B is on the same subnet of machine A.
Which is the correct way to enable reception of multicast frames from different subnets?