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README.md

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+# Docker Volume Backup
+
+A simple script which creates tarballs from docker volumes and restores
+them.
+
+## Usage
+
+### Backup a single volume
+
+`./dvbackup.sh backup <volume_name> <path/to/tarball.tar>`
+
+Creates a tarball from the contents of the volume.
+
+### Restore a single volume
+
+`./dvbackup.sh restore <path/to/tarball.tar> <volume_name>`
+
+Restores the tarball into the volume. *This is destructive*, all old
+contents will be removed from the volume. The volume must already exist.
+
+### Backup all named volumes
+
+`./dvbackup.sh backup_all`
+
+Creates backups from all volumes which do not only contain the character
+set `[0-9a-f]`.
+
+This command will output a `<volume_name>.tar` file for every found
+volume in the current working directory.
+
+### Restore volumes
+
+`./dvbackup.sh restore_all [volume.tar...]`
+
+Restores all given tarballs into their respective volumes. The volumes
+must already exist and the operation is *destructive* in the same way
+as the `restore` operation. The default behaviour is to ask before
+continuing, this can be overridden by setting `DVB_I_KNOW_WHAT_I_DO=y`.
+Volumes can be created implicitly by setting `DVB_CREATE_VOLUME=y`.