OpenVPN

Server configuration file

sudo nano /etc/openvpn/server.conf

Restart OpenVPN Server

sudo sysctl restart openvpn@server

References

1. How To Set Up an OpenVPN Server on Ubuntu 18.04

2. A highly secure OpenVPN 2.4 configuration in 2018

3. Reference manual for OpenVPN 2.4

4. Expanding the scope of the VPN to include additional machines on either the client or server subnet.