A normal VPN links one local network to another - via a gateway router. If you are on a laptop on the 192.168.1.0 network and the VPN is up you will be able to access devices on the 192.168.2.0 network - the remote network securely over the VPN.
Some network services are designed not to work or be aware by default of remote networks, you will have to manually let them know that services exist on the remote LAN subnet so they can access them.
Hopefully someone here who knows more about apple tech can help, but I suspect you can add a remote device (or connect to server in the finder) using an IP ie connecr to to server with afp://192.168.x.y where the x is the network its on and the y is its internal IP.
Martin thank you very much for all your help, I really appriciate it!
As for Peplink (support) I am disapointed. I very clearly stated what I wanted and they told me that all I needed to do was to enable this PEP VPN and the remote offices would be merged as one.
After all the pitfalls and little details that seem to obvious for mere mortals to establish the connection (no mannual mentions to use the different ip ranges on the lan…)
I am now facing an other hurdle that has not been explained to me by Peplink to make things work… 10 hours work and counting.
You might try enabling bonjour forwarding. Go into LAN settings, right at the bottom there is the Bonjour forwarding Settings. Enable that then set the network with the stuff you want to access in the ‘Service Network’ dropdown (so the VPN connection) and your local network in the ‘Client Network’ dropdown and hit Save and Apply.
I’ve never used bonjour forwarding myself - I think that’s how you configure it.
That is exactly whats happening. You can now route traffic securely using the VPN over the internet between your networks. One network is connected to the other. They are not wrong about that. And you can configure it exactly as you describe, where one network extends seamlessly across the internet to another physical network as an extension. This is called layer 2 routing. It is possible but requires a little additional config.
See here Peplink | Pepwave - Forum
