How to Auto-Unlock LUKS2 Encrypted Disks at Boot with Clevis and Tang

The Problem Full disk encryption is great — until you reboot a headless server at 3am and realize you need to type a passphrase with no keyboard attached. Every reboot now requires manual passphrase entry. That's... not great when your server is a headless VM sitting in a datacenter rack in another city. Enter Clevis and Tang. Together they let your server auto-unlock its LUKS2 volume at boot — but only when it can reach your Tang server on the network. No Tang server reachable? No unlock. It's