Editing User:Nomaster/Backup (section)

== Initial Setup ==

'''I assume the external drive is /dev/sdb. If you have no idea about this, stop right now and come back when you know.'''

First, make sure, the external drive is clear to use. So mount it and have a look at the files if present.

Overwrite everything with zeroes.

  sudo dd if=/dev/zero of=/dev/sdb bs=1024

Format the drive

  sudo cryptsetup luksFormat /dev/sdb

(follow the instructions)

Open the crypto container

  sudo cryptsetup luksOpen /dev/sdb backup

Create a BTRFS file system

  sudo mkfs.btrfs /dev/mapper/backup

Mount it (with compression)

  sudo mount -o compress /dev/mapper/backup /mnt

Create a subvolume

  sudo btrfs subvolume create /mnt/nomaster # <- insert username here

Unmount, close and continue with '''daily routine'''.

  sudo umount /mnt
  sudo cryptsetup luksClose backup