Is it possible to get unicast packet from one interface and forward it as broadcast to other interface? Something like dst-nat to 255.255.255.255 I know it sounds strange, but I'm just asking. In fact, I would like to "transform" incoming unicast UDP stream from internet as multicast to my network.

that's interesting - when you dst-nat udp packet to multicast address (for example, 234.0.0.1) - the packet simply disappears. none of 'forward', 'input' or 'output' firewall filter chains catches it

MT Staff, any comments?..