A few months ago I recieved a Yubikey 5C from my employer. I never got into it but today I took the time to delve into it and to set it up.
What is a YubiKey
Simply: The YubiKey is a device that makes two-factor authentication very simple. Instead of a code being texted to you, you press a button on your YubiKey. Each device has a unique code built on to it, which is used to generate codes that help confirm your identity. Press the button and you can log in.
The YubiKey can also be used to sign and decrypt GPG messages and it can be used for SSH authentication.
The Yubikey has a few interfaces. Every interface has a few slots that can be configured. The important interfaces for me are the OpenPGP and the PIV interfaces. The OpenPGP has 1 interface for your PGP keypair, and the PIV interface has 25 interfaces.
I will take this opportunity to create a new PGP key-pair on the OpenPGP slot that I will publish on my contact page. And I will use one PIV slot for my new SSH private key.
I have used Filippo Valsorda’s Yubikey-agent to setup the SSH key on the PIV slot. And GPG to create the GPG keypair on the YubiKey.