How to forward SSDP (dlna) traffic through tap openvpnvpn to a distant network?

Question

openvpn

There is a tap openvpn tunnel of two networks. raised on openwrt routers. Server with white ip. client gateway with grey. There is a dlna device in the LAN with a gray ip. but multicast does not go through vpn by default. And other traffic without problems. The whole network is like a LAN. Including a phone that is also a client. Actually, how to send ssdp traffic through vpn and then make multicast from the vpn server. I hope I'm being clear. Googled the smcroute package. But what should the config look like? and where to try to configure it if there are two openwrt devices (client-gateway and server)

Answer 1

On the openvpn server, specify the TAP device in the settings, connect it to the bridge with your local interface connected to your local network.
If the client is also a server on a different network (you need to combine networks), then on it also connect the tap device into a bridge (on a windows bridge). If the client is just a client, nothing needs to be changed, it will have full access to the server's local network.
I'm not an expert, I couldn't do such a scheme with the openvpn config itself, so I did it with external scripts.
As a result, from the point of view of machines in both networks, it will be one single local network, multicasts will go without problems, the only thing to take care of is that there is no duplication of dhcp and other infrastructure.