I'm trying to set up an authentication scheme for Ubuntu using the pam files.
However, I cannot figure out how to have two separate methods of authentication.
I've set up a Yubikey authentication, however, no matter what, the console prompts for both password and yubikey OTP.
Both have to be correct, however, what I want is for a prompt for the Yubikey, if success, login.
If the Yubikey auth fails, then prompt for a password.
But no matter what, I get a prompt for both yubikey OTP and password.
required, sufficient keywords don't seem to make a difference.
I'm having trouble figuring out how to stack auth configurations like this.
I want to authenticate by method A.
If A fails, attempt to authenticate by B.