Back up a named volume to an archive
Low risk
What do risk levels mean?
- Read-only
- Inspects state without changing anything.
- Low risk
- Reversible with a routine follow-up command.
- Medium risk
- Changes state; undo path documented.
- Destructive
- Deletes or overwrites; confirmation required.
Archives the contents of a named Docker volume into a compressed tar file in the current directory, using a throwaway container. The volume is only read.
dockervolumebackup
Parameters
Name of the Docker volume to back up.
Commands
Confirm the volume exists before backing it up
docker volume inspect <volume>Archive the volume's contents into a compressed tar file in the current directory
docker run --rm -v <volume>:/data:ro -v "$PWD":/backup alpine tar czf /backup/<volume>-backup.tar.gz -C /data .Verification
tar tzf <volume>-backup.tar.gzThe archive lists the files that were in the volume.
Undo
Not undoable
The volume was only read, so there is nothing to undo there. The backup created a tar file in the current directory; delete it manually if it is not wanted.
Pitfalls
- For consistent backups of databases, stop or quiesce the container writing to the volume first; a live copy can capture a mid-write state.
- The volume is mounted read-only (:ro), so the backup container cannot modify it.
- The Windows variant assumes PowerShell; in cmd.exe replace the working-directory reference accordingly.