Hi all, I am having trouble with getting DLNA to work from my NAS to my TV's on separate VLAN's.

Current set up is TV is on VLAN5/IOT LAN.

NAS with DLNA is on VLAN 1.

Inter-domain routing is enabled across VLAN 1 and 5.

Firewall is set up to block all traffic from and to VLAN 5.

Firewall is set up to allow traffic to and from all LAN's to the Sony TV.

I have installed Avahi MDNS reflector on a PI that sits on it's own VLAN and is inter-domain routed with both VLAN 1 and VLAN 5. It seems to be working as I can now cast from a laptop on VLAN 1.

My knowledge on networking starts getting a bit wobbly at this point, DLNA is not working on VLAN 5 from the source on VLAN 1. I have read about IGMP snooping but don't totally understand it, from my understanding, the multicast broadcast packets are being replicated across both VLAN's with Avahi and from a networking point of view they can talk to each other so I'm not sure what to do now.

I have a DrayTek 2860 router which has an IGMP section although it looks like it relates to WAN to LAN, there is a PVC/VLAN option, not entirely clear on what this does or how IGMP proxies work. It also has a IGMP snooping option which I have enabled but not sure what this is doing. The TV's are also connected to a managed switch which has IGMP snooping on also. All I know is IGMP is layer 2, which I think is the reason the wirewall options have no affect, I'm guessing that MDNS broadcast packets are layer 3 which is why the casting is working across VLAN's but I think in theory this should let the TV's at least detect a DLNA server?

Obviously I'm out of my depth here, would appreciate some insight and perhaps a solution without buying extra equipment.

Kind regards,

Will

I believe your problems are caused by the use of broadcasts within DLNA to advertise/find services. In general, broadcasts do not travel across networks, even if those networks appear quite 'local', like VLANs or VPNs. AIUI, the underlying protocol used is SSDP .

I have the same issue - the TV & Sky Box sit on a 'Media VLAN' (there was originally a VM Tivo, with a direct connection to VM's network, which drove this requirement). My DLNA server runs on a PC, which had to have a separate network connection to this VLAN, to make it work. (Fortunately, it's a Virtual Machine, so it's only a 'virtual' network adapter and connection).

If I need temporarily connect to this VLAN from elsewhere, I have to swap SSID's on the device to one that is on the 'Media VLAN'.

I never got it to work across the VPN to another property, probably for the same reasons.

I believe SSDP needs some kind of a proxy (not IGMP) to help it cross network boundaries, which Draytek routers don't provide. You might be able to find something that runs on a Pi though...

I got this working by using udpbroadcastrelayredux and IGMPProxy on the PI with 2 vlans on the primary NIC. Didn't take much configuration, I think IPOptions has to be allowed on your firewall however I didn't do a test to fail on this yet by disabling it.

Examples for the UDPBroadcastRelayRedux:
mDNS / Multicast DNS (Chromecast Discovery + Bonjour + More)
./udp-broadcast-relay-redux --id 1 --port 5353 --dev eth0 --dev eth1 --multicast 224.0.0.251 -s 1.1.1.1
SSDP (Roku Discovery + More)
./udp-broadcast-relay-redux --id 1 --port 1900 --dev eth0 --dev eth1 --multicast 239.255.255.250

These the examples from the github repository, I changed the interfaces to my own VLAN ID's obviously, I think this basically enables the protocols described, including the traffic for DLNA to be routed across the VLAN's.

My IGMP proxy conf:
##

---

## Configuration for eth0 (Upstream Interface)
##

---

phyint eth0.12 upstream ratelimit 0 threshold 1


##

---

## Configuration for eth1 (Downstream Interface)
##

---

phyint eth0.5 downstream ratelimit 0 threshold 1


##

---

## Configuration for eth2 (Disabled Interface)
##

---

phyint eth0 disabled

I think IGMPProxy forwards the multicast broadcast packets back and forth for Multicast/UPNP/SSDP whatever resources/group joining.

UDPBroadcastRelayRedux is on git hub, just cloned the resource and edited the conf in /etc/.
IGMPProxy can install from apt.

Anyway Chromecast, DLNA works, even my SMB server showed up so guess it's fowarding SMB broadcasts too which wasn't needed as I manually pointed the SMB clients on the TV to the NAS, hopefully this helps someone else out.

Will

Well done

It could be you're proxying more than is strictly necessary, but it can always be fine tuned. Do you have a link to it on Github; I couldn't find it with a search

Here's the original project: https://github.com/marjohn56/udpbroadcastrelay
I went for the redux: https://github.com/udp-redux/udp-broadcast-relay-redux
Both worked fine but assume the redux is being actively developed.

Ta