An update for the Raspberry PI 4 backup appliance (last post). Raspberry PI specific changes:

• Upgrade Linux kernel to 5.4.y. This allows e.g. a swap file on the system disk
• Removed the USB 3.0 UAS driver, since it doesn’t seem to work (with the disks I tested it with — see also this thread). This makes USB disks slower, but at least it works reliably
• Use xchacha12+adiantum as system disk encryption method since RPI4 doesn’t have AES CPU instructions. This significantly increases performance
  
  If you want to use it manually outside the appliance use
  cryptsetup luksFormat --cipher xchacha12,aes-adiantum-plain64 --type luks2 --sector-size 4096
  to format the encrypted disk

Download the image for the SD card.

Write the image to the SD card using e.g. Win32 Disk Imager.

Discussion

Discuss the Infscape UrBackup Appliance here.