I know it’s a mouth full.. but the few documents I found on the web were good yet at the same time still left some questions unanswered. So have a look at the PDF and I hope you’ll get it working. Leave a post if it helped you!
Extending-a-Debian-OpenVPN-server-with-Multi-Factor-Authentication-via-Google-Authenticator-1
WeatherBilthoven, Netherlands13:59, 13:59, Mon, Jun 16, 202524°Cscattered clouds
wow! it worked for me!
tested on Ubuntu with pivpn installation
thanks for posting this valuable info. I’m not sure the PDF is accessible from this post. Here’s the direct link for others.
https://ulimit.nl/wp-content/uploads/2019/08/Extending-a-Debian-OpenVPN-server-with-Multi-Factor-Authentication-via-Google-Authenticator.pdf
the auth requisite is a single line, it looks like 2 lines in the pdf.