This is now built into Docker Desktop's Dashboard UI (Volumes Tab) which has more features, but I'll keep this tool around for those not using Docker Desktop.

Vackup: (contraction of "volume backup")

Easily backup and restore Docker volumes using either tarballs or container images. It's designed for running from any host/container where you have the Docker CLI.

Note that for open files like databases, it's usually better to use their preferred backup tool to create a backup file, but if you stored that file on a Docker volume, this could still be a way you get the Docker volume into an image or tarball for moving to remote storage for safe keeping.

export/import commands copy files between a local tarball and a volume. For making volume backups and restores.

save/load commands copy files between an image and a volume. For when you want to use image registries as a way to push/pull volume data.

Usage:

vackup export [OPTIONS] VOLUME FILE Creates a gzip'ed tarball in current directory from a volume

• --owner=UID[:GID] Change the ownership of the exported archive on Linux (won't have any effect on macOS)

vackup import FILE VOLUME Extracts a gzip'ed tarball into a volume

vackup save VOLUME IMAGE Copies the volume contents to a busybox image in the /volume-data directory

vackup load IMAGE VOLUME Copies /volume-data contents from an image to a volume

Download the vackup file in this repository to your local machine in your shell path and make it executable.

sudo curl -sSL https://raw.githubusercontent.com/BretFisher/docker-vackup/main/vackup -o /usr/local/bin/vackup && sudo chmod +x /usr/local/bin/vackup

Vackup includes a comprehensive test suite using Bats (Bash Automated Testing System) that ensures compatibility across macOS, Linux, and Windows WSL.

# Install Bats first
# macOS: brew install bats-core
# Ubuntu/Debian: apt-get install bats

# Run all tests
./test/run-tests.sh

# Run with verbose output
./test/run-tests.sh -v

# Clean up test resources first
./test/run-tests.sh -c

• All four commands (export, import, save, load)
• Error handling and edge cases
• Cross-platform compatibility
• Data integrity and round-trip consistency
• Files with special characters and complex directory structures

See test/README.md for detailed testing documentation.

If any of the commands fail, the script will check to see if a VACKUP_FAILURE_SCRIPT environment variable is set. If so it will run it and pass the line number the error happened on and the exit code from the failed command. Eg,

# /opt/bin/vackup-failed.sh
LINE_NUMBER=$1
EXIT_CODE=$2
send_slack_webhook "Vackup failed on line number ${LINE_NUMBER} with exit code ${EXIT_CODE}!"

export VACKUP_FAILURE_SCRIPT=/opt/bin/vackup-failed.sh
./vackup export ......