Palo Alto Global Protect VPN MFA

Is it possible to use Duo’s capabilities for Yubico OTP with Palo Alto Global Protect and Duo? If so, does it require a specific setting for the Duo Authentication Proxy?

Yes, we’re currently using the Duo Auth Proxy for GP and I can confirm that Yubico OTP works.

Thanks, can you describe or point me to a document describing the settings required for this?

There are no additional settings (beyond the fact that the user needs to have the YubiKey token assigned by a Duo admin first). The user just appends the YubiKey OTP to their password as the passcode as described here and here.