# Borgbackup Script

Once set up, this script helps create backups with `borg` in a very convenient way.

In fact, it's just a slightly more elaborated version of
the [example](https://borgbackup.readthedocs.io/en/stable/quickstart.html#automating-backups)  in the official `borg`
documentation. It mainly focuses on the use of environment variables and also enables the distinction between manual and
automated backups.

## Preparation

### Install Borg

The `borg` packages provided by package managers are usually not up to date. It is better to install borg via `pip` in a
virtual environment.

Download dependencies.

```bash
sudo apt-get install python3 python3-dev python3-pip python3-virtualenv \
libacl1-dev libacl1 \
libssl-dev \
liblz4-dev libzstd-dev libxxhash-dev \
build-essential \
pkg-config python3-pkgconfig

sudo apt-get install libfuse-dev fuse    # needed for llfuse
# or
sudo apt-get install libfuse3-dev fuse3  # needed for pyfuse311
```

Prepare virutal environment.

```bash
sudo mkdir /opt/borg && cd /opt/borg
sudo pip3 -m venv borg-venv
```

Install `borg` via `pip`.

```bash
source borg-venv/bin/activate
pip install -U pip setuptools wheel
pip install pkgconfig

pip install borgbackup
# or
pip install borgbackup[llfuse]  # to use llfuse
# or
pip install borgbackup[pyfuse3]  # to use pyfuse3

```

Link `borg` binary to `$PATH`.

```bash
cd /usr/local/bin
sudo ln -s /opt/borg/borg-venv/bin/borg borg
```

### [ If the `borg` repository should be located on a remote server ]

**IMPORTANT:** `borg` must be installed also on the remote server!

Generate a dedicated ssh key for every user which will create backups.

```bash
ssh-keygen -t ed25519  # Don't set a password!
```

Print public key.

```bash
cat $HOME/.ssh/id_ed25519.pub
# Example output:
# ssh-ed25519 AAAAxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx someuser@somehost
```

Add the public key to your `authorized_keys` file on the server.

```bash
# ON REMOTE SERVER
echo 'command="borg serve --restrict-to-path ~/backups/<user>/<host>",restrict ssh-ed25519 AAAAxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxxx someuser@somehost' >> $HOME/.ssh/authorized_keys
```

### Set up Borgbackup Script

Download the repository.

```bash
cd ~/Downloads
wget https://gitea.extrasolar.space/marc/borgbackup_script/archive/main.tar.gz
tar xzf main.tar.gz
mv borgbackup_script /opt/borgbackup
```

Copy the example environment file to the home directory(s) of the user(s) who will create backups. Then configure
the `.borg-env` file.

```bash
cp /opt/borgbackup/.borg-env.example $HOME/.borg-env
sudo chown $USER. $HOME/.borg-env
sudo chmod 700 $HOME/.borg-env
nano $HOME/.borg-env
```

- [ If the borg repository is located on a remote server: set the right path to the dedicated ssh key ]
- Define the path to your borg repository
- Set a strong passphrase
- Define everything you want to include in your backup as an **absolute path** in the `BORG_TARGETS` array

Make the script executable.

```bash
sudo chmod +x /opt/borgbackup/borgbackup.sh
```

Link the script to the `$PATH`.

```bash
cd /usr/local/bin
ln -s /opt/borgbackup/borgbackup.sh borgbackup
```

### Logs

Create a logfile with read and write permissions for every user.

```bash
sudo touch /var/log/backup.log
sudo chmod 666 /var/log/backup.log
```

Later, each backup procedure gets logged to that file.

### Initialize `borg` repository

```bash
source $HOME/.borg-env
borg init --encryption=repokey
```

Don't forget to export your repository key and store it in a *very* safe place. The key can be exported in three
different formats:

```bash
borg key export /path/to/repo > encrypted-key-backup
borg key export --paper /path/to/repo > encrypted-key-backup.txt
borg key export --qr-html /path/to/repo > encrypted-key-backup.html
```

## Usage

The backup script can be used to create backups either manually or scheduled.

### Manual backup

Manual backups will not be pruned automatically. They are prefixed with `man`.

To create a manual backup just type:

```bash
borgbackup
```

### Scheduled backups

Scheduled backups will be pruned automatically. There will be kept:

- 7 daily backups
- 4 weekly backups
- 6 monthly backups
- 2 yearly backups

Scheduled backups are prefixed with `auto`.

The scheduled backups can be automated by using `cron`.
To create scheduled backups, place this line in your `crontab` (edit with `crontab -e`):

```
0 3 * * * export BORG_RSH='ssh -oBatchMode=yes' && /usr/local/bin/borgbackup auto /dev/null 2>&1
```

## Using `borg`

Please refer to the [official documentation](https://borgbackup.readthedocs.io) to learn how to use `borg`.

**Tip:** Before you use a borg command, `source` the `.borg-env` file. This way, you do not have to type the path to the
repository or the password.

```bash
source $HOME/.borg-env
borg info
```