Currently using a early generation Yubikeys. Guide from here is quite easy to follow. https://developers.yubico.com/yubico-pam/ https://developers.yubico.com/y

Currently using a early generation Yubikeys. Guide from here is quite easy to follow. https://developers.yubico.com/yubico-pam/ https://developers.yubico.com/yubico-pam/ I do like the solution as having no ongoing costs.