VPN server and dial in client are using same subnet

[amigaituk]

Please let me know if this is possible so I can make the change on the server's subnet if not

VPN server and client are at different physical locations behind their own routers

As a test I connected to the VPN server from a different physical location but this was using a different subnet and I was able to get an IP address from the server and browse the internet

When I connect from the client that has the same subnet as the server, I am unable to connect to the internet

I can see the default gateway is missing on when connecting from the client with the same subnet, and I can appreciate the traffic is unable to be routed to the correct physical location over the VPN because it is normal practice to connect with different subnets but i was hoping this was only the case when doing a LAN to LAN site link

It would be a nuisance having to reconfigure the server's subnet as the site has a BT VDSL router which if my customer decided to factory reset when I am on holiday they would mess everything up and I would have to deal with it over the phone

If for example I had 250 clients that are connecting how am I to know every single one's subnet without asking them to remoting in and setting up the VPN, I would need to guess a subnet that no one else is using on the server and hope no other client is using it, it would be unlikely that I would be this unlucky but it might happen although most end users are using class C subnets of 192.168.0.0 192,168,1.0 192.168.2.0 and perhaps a few others like Buffalo who I think use 192.168.16.0

Also, if anyone knows the answer to this question please let me know, it is just in theory though

The customer has a Draytek Vigor 2830n v2 and I can easily set up a VPN on that in L2TP over IPSec mode, I am curious if both server and client have the same subnet if the Draytek software is smart enough to route the traffic over the VPN accordingly? I will ask their tech support and update this post once I know, it's just in theory and I don't want to use that router as I really like SoftEther and want to roll it out to other customers

This is my first install of SoftEther, I am not in anyway and expert but I can understand the basics of networking hopefully demonstrated above in my post

[amigaituk]

Just spoke to Draytek and they said if client and server are on same subnets and a client PC tries to contact an IP and there are 2 devices using the same IP (one on each physical site) the local side will get priority

So I should imagine it is just easier to change the server side subnet for SoftEther to work correctly and if the customer needs to factory reset their BT ADSL router I will have to stress to them that need to know how to change the router back to the correct subnet

I think I will plan ahead and designate more than 1 static IP on desktops in the office so that one of them can be used to administrate the BT router in such an event

[thisjun]

What is your purpose of VPN?