I have a python application that receives multicast packets from one of the ethernet ports set to a static ip on a windows machine. The other ethernet port is a usb-eth dongle configured for another network (dhcp).
When running, wireshark shows the multicast packets arriving on the eth port I expect, however these packets never get all the way up to python.
I swapped the ethernet ports (both cables and settings) so that the static network now receives multicast on the dongle, and now the python application is successfully getting the packets. However, after a reboot cycle the problem has resurfaced and switching the ethernet ports hasn't solved it again.
My knowledge of routing in windows is pretty limited... I have two questions: 1) What could be going on here? 2) How can I 'pin down' the ethernet port that is supposed to get the multicast so my setup is stable?