vbart

Volume Backup And Restoration Tool for Docker

Why is backing up named docker volumes so hard? There's an extension for Docker Desktop, but I just want a simple, easy to use, command-line tool that allows me to backup and restore my named docker volumes. That's what vbart does.

With vbart you can:

• Backup a single named volume.
• Backup all active named volumes on your host.
• Backup just the volumes you list in a separate file.
• Restore a single backup to a named volume.

All backups are stored in compressed (xz) tar archives. Once you create a backup, you can copy it off-host, install it on another machine, share with friends, etc.

Installation

The preferred way to install vbart is with pipx:

pipx install vbart

Alternatively, you can create a separate virtual environment and install it the traditional way:

pip3 install vbart

Usage

For an overview, run:

vbart -h

Backup a Single Volume

vbart backup volume_name

For example, to backup a volume named mysql_db, use:

vbart backup mysql_db

vbart will then create a backup file in your current working directory named:

YYYYMMDD-mysql_db-backup.xz

Backup Multiple Volumes

vbart backups [-v VOLUMES]

Note the plural command name (backups as opposed to backup). VOLUMES is the optional name of a textfile that contains case sensitive volume names (one per line) that you want to backup. Within VOLUMES blank lines and lines beginning with # are ignored, so you can comment the file if you wish.

If VOLUMES is not specified, all active docker volumes on the current host are backed up. All volume backups are saved in the current working directory and named as:

YYYYMMDD-{volume_name}-backup.xz

Restore a Single Volume

vbart restore backup_file volume_name

The first argument (backup_file) is the compressed tar archive you created when you made a backup. The file must have a .xz extension.

The second argument (volume_name) is the named volume to create from the backup. If the named volume already exists, vbart will terminate with no action. Otherwise, a new empty volume will be created with the given name and the backup will be restored to that volume.

Refresh vbart

If vbart is interrupted during execution (e.g. hitting Control+C), then there may be dangling docker containers that hang on to existing volumes. Running the refresh command will clear those dangling containers.

Also, when you run vbart for the first time, it creates a small (alpine-based) docker image to perform the actual backups. This image is called vbart_utility. The refresh command also deletes the utility image, causing it to be recreated the next time you run vbart.

To refresh vbart, use:

vbart refresh