Discover devices on another subnet with DrayTek router with Home Assistant

[Pegasus829]

I have Nest mesh set up on 192.168.86.x, that is connected on LAN2 (192.168.2.x) of my DrayTek router (192.168.1.1). LAN1 is used for wired devices with both LAN1 & 2 connected via inter LAN. I can ping the devices on LAN2 but they are not discoverable.

Should I change the Nest Router LAN IP to 192.168.2.2 to allow for device discovery?

[MichaelP]

Hello @Pegasus829 

The Nest WiFi Router you have connected to your DrayTek router is itself a router and a firewall. So, it is creating a new "inner" network inside the one being created by your DrayTek router. That means it will allow some limited connectivity between devices on this "inner" network and the devices on your "outer" network. In particular, the protocols used for autodiscovery are designed to work on a single network – they won't go through a firewall. Ideally, your wired and wireless devices would all be on the same network instead of being separated by a firewall. As I see it you have three options:

1. Connect your wired devices to the Nest WiFi Router's LAN Ethernet port so they are on the same network as the wireless devices. You may need to use an inexpensive unmanaged Ethernet switch to make more ports available. If you go this route, you may find you don't need the DrayTek router at all, and eliminating it would remove the double-NAT you currently have.
2. If – and only if – you have a single Nest WiFi Router unit with no mesh-connected secondary units, you could set it up in bridge mode, which would put all of your wireless devices on the same network as your existing wired devices as they are currently connected. But, that's a big "if" – most people who have Nest WiFi use it for the mesh expansion, and that isn't supported when the primary unit is in bridge mode. You also lose a number of other features, including guest WiFi, safe search, family schedules, etc.
3. Live with the separation.

[Jeff]

Thanks for all the info, @MichaelP!

Hi Pegasus829,

I just wanted to jump in real fast to see if you saw MichaelP's reply and to see if you still needed some help on this or if you were able to get it sorted out. If you are still needing some help, just let us know and we'll be happy to continue helping.

Thanks,
Jeff

[Jeff]

Hey again Pegasus829,

I just wanted to follow up once more to see if you were still needing some help here. If so, just let us know.

Thanks,
Jeff

[Jeff]

Hi everyone,

Just one quick final check in here since activity has slowed down. We'll be locking the thread in the next 24 hours, but if you still need help, I would be happy to keep it open. If there's more we can do, just let me know.

Thanks,
Jeff