[Encryption and auto-start]

You would remove the key after booting/rebooting, as I do now with my windows machine, if I'm away from home my wife has a copy of the USB key so she can restart the Windows server, to access her files.

I'm looking to replace the windows machine with Unraid, so the same method would be helpful.

[Encryption and auto-start]

 

All the methods above are using servers on the lan or remotely, which I can see the use case for, but could Unraid also use a similar method as Bitlockered Microsoft Windows, using an inserted USB flash drive which has the keyfile on it.