Currently, I have two VPN clients on most of my devices:

  • One for connecting to a LAN
  • One commercial VPN for privacy reasons

I usually stay connected to the commercial VPN on all my devices, unless I need to access something on that LAN.

This setup has a few drawbacks:

  • Most commercial VPN providers have a limit on the number of simulations connected clients
  • I either obfuscate my IP or am able to access resources on that LAN, including my Pi-Hole fur custom DNS-based blocking

One possible solution for this would be to route all internet traffic through a VPN client on the router in the LAN and figuring out how to still be able to at least have a port open for the VPN docker container allowing access to the LAN. But then the ability to split tunnel around that would be pretty hard to achieve.

I want to be able to connect to a VPN host container on the LAN, which in turn routes all internet traffic through another VPN client container while allowing LAN traffic, but still be able to split tunnel specific applications on my Android/Linux/iOS devices.

Basically this:

   +---------------------+ internet traffic   +--------------------+           
   |                     | remote LAN traffic |                    |           
   | Client              |------------------->|VPN Host Container  |           
   | (Android/iOS/Linux) |                    |in remote LAN       |           
   |                     |                    |                    |           
   +---------------------+                    +--------------------+           
                      |                         |     |                        
                      |       remote LAN traffic|     | internet traffic       
split tunneled traffic|                 |--------     |                        
                      |                 |             v                        
                      v                 |         +---------------------------+
  +---------------------+               v         |                           |
  | regular LAN or      |     +-----------+       | VPN Client Container      |
  | internet connection |     |remote LAN |       | connects to commercial VPN|
  +---------------------+     +-----------+       |                           |
                                                  |                           |
                                                  +---------------------------+

Any recommendations on how to achieve this, especially considering client apps for Android and iOS with the ability to split tunnel per application?

Update:

Got it by following this guide.

  • Prison Mike@links.hackliberty.orgEnglish
    1·
    4 months ago

    I use Tailscale to do this. I install the software on everything I can, but for resources on the LAN that don’t have Tailscale running I use its Subnet Router feature to masquerade the traffic and connect to those clients.

    As for the commercial VPN, it’s a bit more involved. I have a few Exit Nodes (VPS) that take incoming Tailscale traffic destined to the Internet and re-route it via the commercial VPN’s WireGuard network interface.

    This was a huge challenge for me (lots of iptables, ip6tables rules) but I have it down to a reproducible script I can provide if you’d like an example.

    My next goal is to containerize the two VPS servers into one with Docker. Tailscale is a bit annoying that you can’t have multiple Nodes running on the same machine (hence my temporary two VPS solution).

    Note: capitalized terms are Tailscale feature names