I want to implement Multi-factor authentication using my custom rule that is if the login is not being attempted from the last IP address I want to send MFA using text message.
Now I am bit confused with the role and order of Rules , DUO ,Google Auth or Guardian . Can you please help me to clear this out .
For general configuration documentation related to SMS support for multifactor, if you haven’t done so already, you should read:
In relation to your additional requirement of only triggering MFA in certain conditions you should pay particular attention the Customize MFA for Select Users section which shows a sample rule that has built-in support for customizing MFA to particular clients and/or users. You would need to implement similar logic for other custom checks.
Basically, for you scenario (MFA with SMS) Duo and and Google Authenticatior would not be relevant as SMS is associated with Guardian. Then rules would be the additional piece that would let your further customize the MFA experience.