Use HD4 as modem only, with external router


Hi there,

I’m hoping I can use our Max HD4 as essentially a modem only, with a Ubiquiti UniFi USG-Pro-4 gateway/router. Would be for a broadcast vehicle that has UniFi switches and various Ubiquiti networking, so I’d like to just use the Max HD4 as WAN bandwidth only and let the USG do the routing.

I won’t be on the vehicle (finishing up build) for another 2 days, but was hoping to figure this out before I get on and start the network config.

Any tips on how to setup HD4 this way appreciated.



About to start on this in next day or so…any help would be appreciated. Thanks!


Hello @RoverRadio,
Within the MAX range it is possible to turn off the internal Wi-Fi from both the InControl2 portal and the MAX Routers admin console so it will not interfere with your existing services
If your existing vehicle network has a router, let that routers WAN port operate on DHCP. Setup the MAX router on a different subset to the vehicle network with DHCP on the LAN.
My former life was as TV Broadcast Engineer and operator so I’ve an interest in this still. If you want to PM us your details I’d be interested in helping you directly on the basis we can share the solution back here for the community to also learn from.
Happy to Help,
Marcus :slight_smile:


Good Evening
One way of doing this is via port based VLANs and set the cellular modems to IP Passthrough.
Port 1 - VLAN 1 - Cellular 1. Outbound policy forcing all traffic from the MAC address of WAN 1 on UniFi to cellular one.
I’m assuming each UniFi WAN on the has a separate MAC address?
If its done by MAC address you might not even need the VLANs?
Would need a little testing.


Been busy, continuing to work on this as time allows. Here’s a question: the MaxHD4 is set as The UniFi router is set as (all equipment on the vehicle, and there’s a lot of it, has static IP’s of 192.168.3.x).

I have LAN1 on HD4 going to WAN1 on UniFi router. Everything works fine, except for one thing:

I have a piece of equipment (audio codec) that needs to use specific ports. So I need to port setup port forwarding. If I take the HD4 out of the equation, and just plug a connection like a cable modem into WAN1 on the UniFi, I can set port forwarding correctly and it works well.

But if I use the HD4, it doesn’t work reliably.

The piece of equipment has a static IP of Should I setup port forwarding on the MaxHD4 and forward ports 9000-9010 (the ones needed) to, or forward to (UniFi router, which has the ports forwarded to .22 already).

That’s the only thing that doesn’t seem to work as I need.



As both the MAX and the UniFi router are doing NAT you need to set up port forwarding from the HD4 to the UniFi and from the UniFi to the audio device on its LAN.


Perfect, I think that got it working. I had previously (mistakenly, it seems) forwarded it to the IP of the audio device (3.22), but that provided results that worked sometimes but not others. Forwarding it to the UniFi router and letting it take it from there seems to have done the trick.