For quite some time we are using Microsoft's Network Protection Services (aka Radius Server) with the Azure MFA extension (https://learn.microsoft.com/en-us/entra/identity/authentication/howto-mfa-np...). Recently we had the requirement to run the same with FreeRadius. I therefore replicated the MFA push behavior in a shell script. After reading that the rlm_exec module is a very bad place to run long running shell code, I re-implemented the code in perl for use with rlm_perl. You can find my code here: https://github.com/adn77/freeradius-azuremfapush-perl According to this https://wiki.freeradius.org/guide/2FA-Active-Directory-plus-Proxy#freeradius... I was hoping to add a conditional in the authenticate section. That's why I only implemented that function in my main.pm. I also looked at this https://github.com/jimdigriz/freeradius-oauth2-perl for inspiration. I am only starting with FreeRadius and was hoping to get some guidance on how to properly integrate this as an MFA option. Hopefully I have already done 90% of the work and somebody here finds this useful as well. Please reply here or on Github Issues of my project. Looking forward to making this work :) Alex