I’ve been running Duo on OpenVPN Access Server since September of 2021 without any issues. I’m running version 2.10.1 of OPVN AS and version 2.5 of the Duo script.
I installed Duo back in September and everything worked fine. I received Duo prompts for the web interface when logging into the VPN server and when logging into the admin panel for the AS. Just this weekend I tried getting into the AS admin panel. I received the Duo prompt on my phone, approved it and then I get an error on the web page that says “ERR_Too_Many_Redirects”. I tried in a different browser and received a similar message about the page not redirecting properly. It mentions that this could be caused by disabling or refusing to accept cookies. If I delete the trailing text from the AS url I am able to get to the AS admin panel.
I also just updated the AS to the latest version. I don’t recall having this issue on the previous version of the AS, but my memory is a little foggy whether I tried logging into the AS admin panel when I updated the AS last month.
I haven’t tried uninstalling the script, but will give that a try and then reinstall the script later today if I get time and report back.
Other thing to note is that this only happens when trying to access the admin panel. Everything works as expected if I am just accessing the web server or using the VPN client. So I’m not sure if something changed with the AS and how it interacts with Duo.
Any other suggestions/feedback is welcome.