Connect Home Assistant to 2 WIFI networks

Configuration
1

I live outside the US so I connect two Apple TV’s to a router that runs ExpressVPN. This allows me to watch TV in the US. Everything else in the house including TV’s and Sonos are connected to another router.

Is it possible to connect Home Assistant to both networks and control all devices as if they are on the same network?

I’m finding a similar question but I think they are talking about running smart home devices on a guest network and all else on the normal network so it’s a different use case I think.

Thanks.

2

At minimum, you’ll need 2 wifi adapters on whatever device you run HA on

3

Asking for trouble unbless the hardweare has enopugh horsepower etc… better to go with etherneet. I’ve got a RPI4 that is on two separate vlans at the same time - you can add multiple vlan interfaces to the same ethernet connection (I know, nbot quite the same thing). But you should go with ethernet if at all possible

4

If you have a Pi, connect the Ethernet to this network, and the WiFi to your Apple TV’s network. If using another type of computer, you can do the same if it has both Ethernet and WiFi.

5

Changed the title to “how to harden my IOT vlan security”:

I am learning how to implement a firewall to separate my IOT vlan from my non-IOT vlan and thought the below might help. I have left my HA host on the non-IOT vlan and maybe that was a mistake 0 to rectify later as I learn - however -

FYI - if you have this IP address for your RPI (my HA host):

192.168.0.12

this would show the connection details from a command line on the host:

ip addr show eth0

(if it was for wifi it might be wlan0 instead)

If you only have one physical ethernet connection to your RPI (or one wifi connection to it) but want it to ALSO be present on an additional VLAN - you have to set up the other vlan of course first - (network with different subnet) with this IP address:

192.168.10.12

then, you can also without buying any hardware you can do this:

sudo ip addr add 192.168.10.12/24 dev eth0.10

(or possibly wlan0.10 for wifi ?)

and your rpi would be reachable from within either subnet by these IP’s (this was my first stepo/stab at starting to separate the IOT vlan (.10) for security purposes):

192.168.0.12
192.168.10.12

Subsequently to undo tha in the future if you want to, would be:

sudo ip addr del 192.168.10.12/24 dev eth0.10