broadcast to docker support

Hi,

I want to enable some audio devices access to my music collection via DLNA. However the DLNA server and clients are on different subnets/vlans. I get the firewall to forward the multicast requests to port 1900 for discovery and it reaches the Unraid server. But since the DLNA server is on a bridge interface assigned to a VLAN Unraid does not forward the multicast packets due to IPVLAN being used in docker.

I do not want so switch the default installation to MACVLAN.

Is there a way to either have one container run in a MACVLAN instead of the default IPVLAN and if so, what would the disadvantage be?

The other way I can think of is running smcroute in a docker, have that docker be network=host and be part of a custom network only consisting of the DLNA server container and the smcroute container. According to some posts in the net that might work if setup correctly. Does anyone have experience with this or another suggestion?

Assuming the smcroute way is something worth trying, how can I attach the DLNA Server and the smcroute not only to the bridge (with a VLAN) or host but have it join the custom network as well. I believe there as an advanced setting for that. Is "&& docker network connect" as a post argument the right way to do this? Moreover how can I persist the custom network setup across reboots (if necessary)? 

And one additional question: For historical reasons my Unraid has two interfaces. eth0 being the one I do not use anymore with a network attached and IP1 and eth4/5 as a bond with VLANs and IP2. Unraid seems to believe that the "primary IP" is IP1. So if I run dockers with network=host the GUI tells me IP1:port as access. The container listens on all interfaces so that is not the problem but maybe the wrong IP information also gets inside the container and if the container service is announcing "its IP address" it would announce the wrong IP1. Is there a way for me to change this without having to get rid of eth0 altogether (which is something I contemplate as well). 

Many thanks for all suggestions!