Possible IP conflict when using Tailscale and a subnet router on a remote LAN?

I just found out about tailscale and have a very rudimentary understanding of how it works.

From what I understand, Tailscale works best when the individual computers run Tailscale clients, and the traffic between them is encrypted, essentially if 2 computers run on my Tailnet, no matter where they are in the world, they will behave like they are on the same LAN.

If I want to set up Tailscale on one computer on my LAN, and want to access my entire LAN that way, I have to set up a subnet router.

From what I understand, if I set up a subnet router on my LAN, which has a router login page at 192.168.0.1, when I connect to my Tailnet from anywhere in the world, I would be able to type in 192.168.0.1 in my browser and get to my home LAN router’s log in page.

My question is this: When I’m on a remote wi-fi (not my home LAN), and that remote LAN also has a router gateway at 192.168.0.1, and I type in 192.168.0.1 in my browser while connected to Tailscale, to get to my home router’s log in page, how will Tailscale determine whether it goes to my home router that’s on my Tailnet through the subnet router, or to the router of the LAN I’m directly connected to?

Hope the question makes sense

Yes, that makes sense.

Unfortunately, when you route between two networks, they need to have a different scope. If you’re going to routinely be connecting from a 192.168.0.0/24 network, then you should set up your network to another block, like 192.168.1.0/24

If that’s not possible, you can also split the subnet. put your home network hosts above .128 if the remote network is all below it, then you can route 192.168.0.0/25 and set the appropriate netmasks on the two networks.

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Thanks. That cleared things up a lot :slight_smile: