acgtek wroteby following this online post ..
Please report the problem to the author of the page.
acgtek wrote:~/openvpn-ca$ ./build-key-server server
Please edit the vars script to reflect your configuration,
then source it with "source ./vars".
Next, to start with a fresh PKI configuration and to delete any
previous certificates and keys, run "./clean-all".
Finally, you can run this tool (pkitool) to build certificates/keys.
The instructions look clear enough ..
Also see:
https://github.com/OpenVPN/easy-rsa/releases