Using Tailscale SubNet Routing and Flex Radio

Alan

There have been others observe that when using TailScale VPN subnet routing, that your Flex Radio does not work, including no audio, no pan adapter streams and DAX not showing audio. All these use UDP broadcast packets, which TailScale subnet routing "captures" never to be seen again by the Flex radio on the LAN.

I wanted to find a solution to allow me to access my home network when away. Normally, TailScale is a device to device VPN, that is easy to set up and secure. But what about the other devices on the home network, like the PG-XL and TG-XL you want to access remotely? You cannot install Tailscale on these devices.

The solution is in setting up the TailScale "advertised" sub net. I have TailScale set up on my AppleTV. The "default" advertised subnet is your subnet starting at "0", with a "24" mask. This will advertise your subnet addresses from ****.****.****.0 to ****.****.****.254. This is all the available address, which your Flex Radio will also reside.

The solution is to first, use a mask of "25" as shown below. This will advertise IPs addresses ****.****.****.0 to ****.****.****.128. Now move your Flex radio to an IP greater than ****.****.****.129. All done.

I like to use DHCP reservations, so just change the IP in the reservation table, or if you prefer static IPs, change that on the Flex radio, If you change the DHCP reservation table, be sure to re-boot the radio, to force it to use the new IP.

Now, the Flex radio is not within the advertised TailScale Subnet router, and will be left alone. All of the Flex UDP broadcasts now work, and for devices within the advertised subnet, you can access them from outside your LAN, as long as you are logged into TailScale.

One hich….no UDP packets will move to the WAN via Tailscale. This is not a problem if you do not use UDP, but what about the genius utilities, that depend on receiving a UDP packet with the connection information? This is a problem.

First, I tested using the "Genius Tools' from my Mac SmartSDR. The tool allows you to enter the LAN IP of the AG, PG or TG. Works great when outside the LAN via TailScale.

Not so much with the AG, PG and TG window utilities. No way to manually enter the IP, it needs to first see the UDP packet with connection info. I built a Node-Red flow to broadcast a UDP packet on the computer's loopback address and appropriate port for each device. Now the utility knows how to connect, even though the UDP is local, not from the actual device at home.

Alan. WA9WUD