backups

Auto backup script. The objectives are the following:

• Have a raspberry-pi RPI (or any other device) doing automatic backups of a remote server SERVER every day
• Backups are incremental, without redundancy, it is easy to get data out of a specific snapshot
• RPI is not vulnerable to physical access (in a reasonable way):
  • The backup disk is encrypted, but the key is not stored on RPI
  • The keys to access SERVER are locked and can be "revoked at distance"
• Conversely, if a malicious access is made to SERVER, backups are not compromised
• If a backup fails for any reason, a notification is sent (via Discord)
• RPI can be accessed remotely, without needing to expose one of its ports

Installation

On a raspbian distribution, this requires:

• The packages cryptsetup sshpass
• a filesystem (in a LUKS device with LUKS_KEY) formatted in xfs or btrf (needs either xfsprogs or btrfs-progs)
• an ssh key locked with SSH_PASSPHRASE to access to the server to backup
• Two urls containing each LUKS_KEY or SSH_PASSPHRASE
• a (Discord) webhook