YubiKey global MFA settings
At the global level, configure the non-FIDO2 YubiKey device method. Users can use a YubiKey device made by Yubico to authenticate into a resource.
To use FIDO2-compliant YubiKeys use the FIDO2 WebAuthn global MFA settings.
You can limit the use of this MFA method in a policy.
- On the left side of the Identity Platform page, click Multi-Factor Methods. 
- Click the pencil icon for YubiKey. - The configuration page for YubiKey appears.  
- To enable or disable the global YubiKey multi-factor method, slide the toggle On or Off. 
- Set any the following configurations. - Yubico OTP - Select this option to give access to a user who has a YubiKey to generate an encrypted one-time passcode (OTP). - OATH HOTP - Select this option to give access to a user who has a YubiKey to generate an encrypted six-, eight-, or nine-character one-time (OTP) event-based passcode using OATH-HOTP. This means that a new one-time passcode is generated for each event. - Passcode length - Set the passcode length at six, eight, or nine digits for your YubiKey and Authentication App methods. 
- Click Save. 
Next steps
Configure a policy on the Multi-Factors Methods tab to allow users to authenticate using non-FIDO2 YubiKeys in the login workflow.