Setting up your own Certificate Authority (CA) and generating certificates and keys for an OpenVPN server and multiple clients.
next tip, for much more security in openvpn is setting:
tls-auth /path/to/ta.key 0
tls-auth /path/to/ta.key 1
first you should generate this cert by:
openvpn --genkey --secret ta.key
and maybe changing the default blowfish alghoritm (128bit) with 256-bit AES by adding: