Take a look into this issue:
Its recommended to use the installimage method from hetzner.
These are clean step-by-step guides on how to setup a hetzner root server from their server auctions called "serverbörse" to get fully-encrypted and remotely unlockable servers with or without different RAID-Systems and with or without LVM.
These guides could work at any other provider with a rescue system or with manually installed servers with little modifications.
- Debian Guide (HWRAID-1 LVM LUKS) Contributed by @leviwheatcroft
- Debian Guide (SWRAID-1 LVM LUKS) Contributed by @sirtoobii
- Debian Rescue mode Contributed by @sirtoobii
- Debian Guide (2 HWRAID-1 LVM LUKS) Contributed by @martinseener (Longer Original Blogpost)
Please contribute!