As discussed in a previous post, multi-factor authentication really makes things more secure. Let’s see how we can secure services like SSH and the Gnome desktop with multi-factor authentication.
The Google Authenticator project provides a PAM module than can be integrated with your Linux server or desktop. This PAM module is designed for for home and other small environments. There is no central management of keys, and the configuration is saved in each users home folder. I’ve successfully deployed this on my home server (a Raspberry Pi) and on my work laptop.