uberspace-backup/README.md

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# Uberspace Backup

[![REUSE compliant](https://api.reuse.software/badge/src.mehl.mx/mxmehl/uberspace-backup)](https://api.reuse.software/info/src.mehl.mx/mxmehl/uberspace-backup)

This Bash script is able to backup directories from Uberspace users (and also
other SSH resources). For Uberspace hosts it can also backup MySQL databases by
copying the backups Uberspace cleverly created for you.

It is designed to work automatically on another server with enough harddisk
space.

## Features

- Transfers files securely via rsync over SSH.
- Encrypts backups with GnuPG, using a public key only. Once a backup is
  encrypted it can only be decrypted with a private key. Make sure to delete the
  private key from the backupping server (after saving it on a more secure space
  of course) to keep your backups even safer.
- If desired, it can delete older backups and only retain a configurable amount
  of backups.
- Rather verbose logs will be written to backup.log.
- With the helper script `ssh-checker.sh` one can automatically test whether the
  hosts provided in the hosts file can be accessed. If not, the little helper is
  trying to put your public SSH key to the remote hosts' authorized_keys files
  by letting you type in the password manually once.

## Configuration

Configuration happens in two files: config.cfg and hosts.csv.

### config.cfg

Everything should be self-explanatory with the comments. Make sure to use the
correct GPG fingerprint, and make sure to have its public key imported by the
user executing the script. No private key has to be installed on the backupping
system (but on the decrypting one of course).

### hosts.csv

This file contains the hosts and its directories that shall be saved. It
consists of two rows separated by `;`. The first one contains a
`username@hostname` combination that will be used to sync files via SSH, and
also as the backup destination directory name.

The latter one contains all source directories that shall be transferred. This
can be absolute file paths, or – if it's a Uberspace host – some special
shortcuts:

- `%virtual` backups the virtual folder of your uberspace host
  (`/var/www/virtual/username/`) where for example the `html` folder is located
  in.
- `%mysql` downloads the latest backup of your MySQL databases that have been
  created by Uberspace themselves (their backup system is quite sophisticated).
- `%mails` downloads the directory `users` in the home directory which contains
  all email files of virtual mail users.
- `%home` simply downloads the whole user's home directory.

You can give multiple locations that shall be backed up. Just separate them by
`|` characters. See the example file for more.

## Process

The script runs the following most important steps:
1. For each host in `hosts.csv`
    1. Check SSH connection
    1. Compose SSH host settings
    1. For each backup source
        1. Resolve special backup sources
        1. Create backup destination
        1. rsync source to destination
        1. tar the destination
        1. gpg-encrypt the destination
        1. Delete older backups
1. Output completion info

## Manual run

You can run `ssh-checker.sh` and `uberspace-backup.sh` manually. Without any arguments given, both will check/backup all hosts.

You can provide an argument to check/backup a specific host. This argument has
to fully match a server's `user@hostname[:port]` declaration as on `hosts.csv`.

## Automatic runs

In order to let the script run regularily, simply put the script's absolute path
in a cron file. For example, run `crontab -e` and insert at the bottom:

```
10 3 * * * /home/archiver/uberspace-backup/uberspace-backup.sh
```

This will run the backups every night at 3:10.

## Known limitations

- Please note that paths like `~` or `$HOME` haven't been tested yet. Use
  absolute paths instead.
- At the moment, the backups don't follow symbolic links. That's why for example
  error logs aren't downloaded when using `%virtual`. Make sure to regularly
  check your backups to make sure all important files are saved.