With the rise of support for multi-factor authentication in popular services and devices, the YubiKey family of hardware tokens has risen in popularity. Hardware tokens are more secure than using SMS as a delivery method because an attacker has to steal them from you and can't do so remotely. Yubico, the manufacturer of the YubiKeys has excellent guides for different use-cases of their tokens, but I found that the one for Ubuntu lacks in the real world: It does not expect an encrypted filesystem and fails
authentication
A 1-post collection