How to connect to a gray-IP server?

Question

Data transfer

Good afternoon!
Tell me how you can organize the following connection:

There is 1 server and 1 client, computers are in different networks, in different cities and different providers.
The server is located behind the router, a gray ip of the format 100.x.x.x comes to the router from the provider. Is
it possible to connect to transfer data remotely from the client to the server, without acquiring a "white" ip on the server? And if so, how?
I tried to set it up via hamachi and fileezilla, but for some reason it didn't work.
Maybe I'm doing something wrong.
Thank you in advance for your help.

Answer 1

white IP will be cheaper.
You also need to raise the VPN to a white IP.
Hamachi could work, as it provides its own server to initialize the VPN. Perhaps misconfigured. But your white IP will be more reliable

Answer 2

To connect, you must have at least one side with external routable "white" ip. If there is none on the server side
1) Maybe on the client side
2) Maybe on the third system side.
In the first case, you can configure vpn in the opposite direction, i.e. the server is the client and the client is the vpn server.
In the second case, no one bothers you to sit at the nat for both the client and the server, and drive traffic through a third system that will act as a vpn server and route traffic.

Answer 3

For those who are not afraid to drive their desktop through a third server - there is TeamViewer, but the connection must be initiated by the server that is behind nat - and then transfer your id in some way to another server that will find it on the TeamViewer server and connect