Is it possible to go through a vpn tunnel in the opposite direction?

Question

VPN

Subject. There is a server to which the client connects via VPN and works, say, in 1C. Is it possible to set everything up so that you can go from the server to the client's machine and work on it using the connection that already exists?
Covert penetration issues are not considered. Those. By default, the client is aware that they want to access the machine and agree to this.

Answer 1

If there is a tunnel, then this means either an L2 or L3 channel already exists, in both cases there is an IP address on both sides. Therefore, you are already walking in both directions. Further customization depends on what you want to do. In a typical case: configure the firewall so that it allows access to the desired software / port, raise this very software. Therefore, it is not just possible, but out of the box it is possible.

Answer 2

You can "walk". As Dmitry Filimonov pointed out that the IPs for the two sides are known, they are either on the same subnet, or routing is configured between them. In this case, the client is the initiator of the connection. Without his knowledge, the server cannot contact him, respectively, here you already need to contact the client's firewall. It probably doesn't allow new connections from addresses other than localhost. So it all boils down to adding rules in the ITU to establish new connections from the server side on specific ports (eg 80 or 22) inside the VPN tunnel.