sfttech / sftbackup

simple periodic backup tool based on borgbackup and snapper

sftbackup

Simple wrapper for borg backup and snapper

• Config file example.

Remote backup setup

You can store the backup over SSH on a remote server.

This even works for multiple clients to one server as borg can jail clients by ssh forced commands.

Client setup

Backup targets:

• Remote server via SSH (you have a borg remote url)
• Local storage (secondary harddrive, a nfs/samba mount, ...)

Remote backup client preparation

If you do your backup remotely via SSH, you need a SSH key first.

• Generate ssh-key for user root
  • Of course you may reuse an existing ssh key, but root has to be configured to use it.

HOME=/root sudo ssh-keygen -t ed25519 -f /root/.ssh/id_ed25519_backup

• Provide your ssh public key in /root/.ssh/id_ed25519_backup.pub to the server operator
• Configure SSH to use the right user and ssh key in /root/.ssh/config:

# example config if your borg backup remote url is "[email protected]:reponame"
Host borgbackup.somewhere.net
    User borg
    IdentityFile ~/.ssh/id_ed25519_backup

Client configuration

• Configure sftbackup in /etc/sftbackup.cfg
• Set password = ... to encrypt the backup
  • To generate a password, you can use pwgen 30 1
  • Note down the password somewhere (to be able to restore the backup!)
• Use repo = ... to specify where to store the backup
  • Remote backup via SSH: repo = [email protected]:reponame
  • Local storage, e.g. external HDD: repo = /mnt/backupdrive
• Adjust other things like paths, excludepaths, ...

Repo creation

• Create the repo: sudo sftbackup init
• This will initialize the borg repo in repokey mode.

Test backup

• Test the creation of the first backup by running sudo sftbackup backup

Automated runs

This is only suitable for devices that are permanently running (e.g. servers)

• Install the sftbackup.timer and sftbackup.service systemd units
• Enable and start the sftbackup.timer

Enjoy your backups!

Server setup

Repo storage:

• Create a borg user on your host: sudo useradd -m borg
• Create the storage directory: sudo mkdir /home/borg/repos.
• Create the authorized_keys file in /home/borg/.ssh/authorized_keys
  • Ensure the .ssh and authorized_keys file belong to user borg

Client access:

• Create a directory /home/borg/repos/clientname (owned by user borg)
• Grant access in authorized_keys:

command="cd /home/borg/repos/clientname; borg serve --restrict-to-repository /home/borg/repos/clientname/reponame --storage-quota 1.5T",restrict ssh-ed25519 client's_ssh_public_key_... root@clientname

• Add --append-only to disallow this client to remove data in its repos (very handy so a server can't delete its own backup when hacked).
• See man borg-serve for further information on how to restrict client access

Restore

• Retrieve and store file(s) from repo
  • use borg extract
• Mount repo as FUSE
  • use borg mount

Contributing

As you might have guessed, you can report issues and submit patches through pull requests easily.

License

GNU GPLv3 or later; see copying.md and legal/GPLv3.