Can you get multicast discovery to cross subnets ?

[guppy 10]

Problem:

I have devices on different subnets ( 192.168.15.x, 192.168.35.x ) and would like for them to be able to discover each other. Specifically I want them so see each others minecraft (bedrock/pocket) worlds.

 

the 15.x network is the "privileged" home network, where as the 35.x network is intended as guest-wifi network with no internet access ( also vpn clients would be given a IP here )

 

currently they cannot see each other - if I add a route with 192.168.15.x to the vpn config then vpn clients can access webservers in this subnet but minecraft clients still can't see each other.

 

My router is a N66 running tomatoUSB and both subnets are entirely controlled by it.

 

Question:

 

Is this even possible? 

If so - how?

 

Any help would be appreciated I currently do not know enough to even successfully google for marginally useful information

 

[guppy 10]

sometimes it just helps asking the question out loud it seems.

 

Advanced > Firewall - has two options for multicast IGMPproxy and Udpxy

 

I think the first one should work, I'll update this post once I've had a change to test

[guppy 10]

sadly IGMPproxy didn't work

 

may have to try compiling https://bitbucket.org/lucasec/mdns-repeater/src

[guppy 10]

for IGMPproxy to work I would need to know the broadcast address and port :<

 

Really wish I could just bleed 224.0.0.0/4 for between subnets