How to set up backups with borgmatic

Installation

To get up and running, first install Borg, at least version 1.1.

Then, run the following command to download and install borgmatic:

sudo pip3 install --upgrade borgmatic

Note that your pip binary may have a different name than "pip3". Make sure you're using Python 3, as borgmatic does not support Python 2.

Other ways to install

Along with the above process, you have several other options for installing borgmatic:

Configuration

After you install borgmatic, generate a sample configuration file:

sudo generate-borgmatic-config

If that command is not found, then it may be installed in a location that's not in your system PATH. Try looking in /usr/local/bin/.

This generates a sample configuration file at /etc/borgmatic/config.yaml (by default). You should edit the file to suit your needs, as the values are representative. All fields are optional except where indicated, so feel free to ignore anything you don't need.

You can also get the same sample configuration file from the configuration reference, the authoritative set of all configuration options. This is handy if borgmatic has added new options since you originally created your configuration file.

Encryption

Note that if you plan to run borgmatic on a schedule with cron, and you encrypt your Borg repository with a passphrase instead of a key file, you'll either need to set the borgmatic encryption_passphrase configuration variable or set the BORG_PASSPHRASE environment variable. See the repository encryption section of the Borg Quick Start for more info.

Alternatively, you can specify the passphrase programatically by setting either the borgmatic encryption_passcommand configuration variable or the BORG_PASSCOMMAND environment variable. See the Borg Security FAQ for more info.

Initialization

Before you can create backups with borgmatic, you first need to initialize a Borg repository so you have a destination for your backup archives. (But skip this step if you already have a Borg repository.) To create a repository, run a command like the following:

borgmatic --init --encryption repokey

This uses the borgmatic configuration file you created above to determine which local or remote repository to create, and encrypts it with the encryption passphrase specified there if one is provided. Read about Borg encryption modes for the menu of available encryption modes.

Also, optionally check out the Borg Quick Start for more background about repository initialization.

Note that borgmatic skips repository initialization if the repository already exists. This supports use cases like ensuring a repository exists prior to performing a backup.

If the repository is on a remote host, make sure that your local user has key-based SSH access to the desired user account on the remote host.

Backups

Now that you've configured borgmatic and initialized a repository, it's a good idea to test that borgmatic is working. So to run borgmatic and start a backup, you can invoke it like this:

borgmatic --verbosity 1

By default, this will also prune any old backups as per the configured retention policy, and check backups for consistency problems due to things like file damage.

The verbosity flag makes borgmatic list the files that it's archiving, which are those that are new or changed since the last backup. Eyeball the list and see if it matches your expectations based on the configuration.

Autopilot

Running backups manually is good for validating your configuration, but I'm guessing that you want to run borgmatic automatically, say once a day. To do that, you can configure a separate job runner to invoke it periodically.

cron

If you're using cron, download the sample cron file. Then, from the directory where you downloaded it:

sudo mv borgmatic /etc/cron.d/borgmatic
sudo chmod +x /etc/cron.d/borgmatic

You can modify the cron file if you'd like to run borgmatic more or less frequently.

systemd

If you're using systemd instead of cron to run jobs, download the sample systemd service file and the sample systemd timer file. Then, from the directory where you downloaded them:

sudo mv borgmatic.service borgmatic.timer /etc/systemd/system/
sudo systemctl enable borgmatic.timer
sudo systemctl start borgmatic.timer

Feel free to modify the timer file based on how frequently you'd like borgmatic to run.

Troubleshooting

libyaml compilation errors

borgmatic depends on a Python YAML library (ruamel.yaml) that will optionally use a C YAML library (libyaml) if present. But if it's not installed, then when installing or upgrading borgmatic, you may see errors about compiling the YAML library. If so, not to worry. borgmatic should install and function correctly even without the C YAML library. And borgmatic won't be any faster with the C library present, so you don't need to go out of your way to install it.