I am trying to etablish an GRE tunnel to my Windows Server 2019, which seems easy enough. Although things get a bit complicated, as I want my applications to bind to the IP on the other side of the tunnel.
My setup would look like this: Visitor -> Mikrotik router (10.10.10.10) --> GRE tunnel --> Server (20.20.20.20) + (10.10.10.10)
I am aware that it would require 3 IPs or so, as I need to route an /28 with the GRE tunnel.
I've seen a few companies do what I'm trying to acomplish eg. x4b.net, but their secret source is hidden in an exe program.
I have tested the setup using an OpenVPN tunnel as a TAP adapter and it is working. However, in regards to performance, this doesn't seem like an optimal solution.
An important note: I do not have access to a router in front of the server (client seen from the tunnel) so it needs to be configured on the server itself.
What I am trying to accomplish is similar to this: https://www.x4b.net/kb/WindowsIPIPTunnel
The solution I am using on Linux looks like this: https://www.lowendtalk.com/discussion/156850/howto-tunnel-ddos-protected-ovh-ip-to-vms-in-other-datacenter
