Proxy, VPN, TOR, and similar services
Hosting of open proxy, open VPN, open DNS resolver, and other public services (including the private or paid ones) that can be used for committing illegal acts online is prohibited on VPS and dedicated servers.
It is prohibited because scammers and offenders make frequent use of such services.
OpenVPN can be installed on your server for personal use. No third party will be able to use this service.