btrsnap

The btrsnap module is written for python 3.x.

Table of Contents

• Installation:
  • General Linux
  • Arch Linux
• The SNAPPATH:
  • Example
• USAGE:
  • snap
  • list
  • delete
  • send

Installation:

• Instructions on btrsnap wiki:

  https://github.com/lenzenmi/btrsnap/wiki/Install

General Linux

clone this git repo to your local system, then install using python.

#Install some dependencies
pip install python-dateutil

#Install btrsnap
git clone git://github.com/lenzenmi/btrsnap.git
cd btrsnap
python setup.py install

Arch Linux

If you are lucky enough to use Arch Linux, there is a python-btrsnap PKGBUILD available on the aur:

PKGBUILD: python-btrsnap

https://aur.archlinux.org/packages/python-btrsnap/

This can easily be automatically installed using yaourt

yaourt -S python-btrsnap

The SNAPPATH:

btrsnap uses a specific directory layout to store BTRFS snapshots. These must be created manually before using many of btrsnap's features.

Requirements:

• It is a directory located on a BTRFS filesystem
• It contains a single symbolic link that points the BTRFS subvolume to be backed up.

It is good practice to organize a collection of SNAPPATHs in a parent directory to take advantage of btrsnap's 'recursive' features.

Example

`-- parent
    |-- photos
    |   `-- target -> /home/photos
    `-- webserver
        `-- target -> /srv/http

In this example, photos and webserver are both valid SNAPPATHS and inside a parent folder.

Note

Symbolic links can be created with the 'ln' command:

$ln -s path target

USAGE:

Note

btrsnap has four main modes of operation. One of these modes must be specified from the command-line.

snap

usage: btrsnap snap [-h] [-r] [-k N | -d YYYY-MM-DD or ?y?m?d?w] PATH

Creates a new timestamped BTRFS snapshot inside of PATH. The snapshot will be
a snapshot of the BTRFS subvolume pointed to by the symbolic link in PATH.

positional arguments:
  PATH                  a directory on a BTRFS file system with a symlink
                        pointing to a BTRFS subvolume

optional arguments:
  -h, --help            show this help message and exit
  -r, --recursive       instead, create a snapshot inside of each directory
                        located inside of PATH

Mutually Exclusive:
  (Optional) - Choose 1

  -k N, --keep N        after creating, delete all but N snapshots
  -d YYYY-MM-DD or ?y?m?d?w, --date YYYY-MM-DD or ?y?m?d?w
                        after creating, delete all snapshots created on or
                        before the entered date. You may enter dates as ISO
                        format or use the alternate syntax ?y?m?d?w where ?
                        can be any positive intager and indicates the number
                        of years, months, days, and weeks respectively

Important

You will need root permissions to delete.

list

usage: btrsnap list [-h] [-r] PATH

Show timestamped snapshots in PATH.

positional arguments:
  PATH             a directory on a BTRFS filesystem that contains snapshots
                   created by btrsnap.

optional arguments:
  -h, --help       show this help message and exit
  -r, --recursive  instead, show summary statistics for all subdirectories in
                   PATH

delete

usage: btrsnap delete [-h] [-r] [-k N | -d YYYY-MM-DD or ?y?m?d?w] PATH

Delete all but KEEP snapshots from PATH, or delete all snapshots created on or
or before DATE

positional arguments:
  PATH                  a directory on a BTRFS filesystem that contains
                        snapshots created by btrsnap

optional arguments:
  -h, --help            show this help message and exit
  -r, --recursive       instead delete all but KEEP snapshots from each
                        subdirectory

Mutually Exclusive:
  (Required) - Choose 1

  -k N, --keep N        keep N snapshots when deleting
  -d YYYY-MM-DD or ?y?m?d?w, --date YYYY-MM-DD or ?y?m?d?w
                        delete all snapshots created on or before the entered
                        date. You may enter dates as ISO format or use the
                        alternate syntax ?y?m?d?w where ? can be any positive
                        intager and indicates the number of years, months,
                        days, and weeks respectively

Important

You will need root permissions to delete.

send

usage: btrsnap send [-h] [-r] SendPATH ReceivePATH

Send all snapshots from SendPATH to ReceivePATH if not present.

positional arguments:
  SendPATH         a directory on a BTRFS filesystem that contains snapshots
                   created by btrsnap
  ReceivePATH      a directory on a BTRFS filesystem that will receive
                   snapshots

optional arguments:
  -h, --help       show this help message and exit
  -r, --recursive  instead, send snapshots from each sub directory of SendPATH
                   to a subdirectory of the same name in ReceivePATH.
                   Subdirectories are automatically created if needed

Important

The ReceivePATH needs to be relative to the top-level BTRFS volume. If you try to use a path relative to a mounted subvolume, this operation will fail!!