Recommended L2TP solution for accessing Rancher?

I’m wanting to setup a VPN service that allows access to Rancher hosted containers.

The use case is such that for access to any Rancher containers in an environment, the user/developer would first:

  1. VPN in, ideally into a VPN server container within Rancher
  2. and then be able to access containers via the Rancher network.

I don’t wish to use OpenVPN as I’d prefer to use native VPN tools on Mac and Linux, etc and therefore use L2TP or IKEv2.

I have tried SoftEther which works perfectly as a standalone container outside of Rancher on the same host (but cannot access, but when instantiating the same container within Rancher, no access is possible. I suspect this is due to the network configuration and the way Rancher runs the overlay.

Does anyone have a solution for this?