rotate-backups 1.0

Simple command line interface for backup rotation

Backups are good for you. Most people learn this the hard way (including me). Nowadays my Linux laptop automatically creates a full system snapshot every four hours by pushing changed files to an rsync daemon running on the server in my home network and creating a snapshot afterwards using the cp -al command (the article Easy Automated Snapshot-Style Backups with Linux and Rsync explains the basic technique). The server has a second disk attached which asynchronously copies from the main disk so that a single disk failure doesn’t wipe all of my backups (the “time delayed replication” aspect has also proven to be very useful).

Okay, cool, now I have backups of everything, up to date and going back in time! But I’m running through disk space like crazy… A proper deduplicating filesystem would be awesome but I’m running crappy consumer grade hardware and e.g. ZFS has not been a good experience in the past. So I’m going to have to delete backups…

Deleting backups is never nice, but an easy and proper rotation scheme can help a lot. I wanted to keep things manageable so I wrote a Python script to do it for me. Over the years I actually wrote several variants. Because I kept copy/pasting these scripts around I decided to bring the main features together in a properly documented Python package and upload it to the Python Package Index.

• Features

• Installation

• Usage

  • Command line

• Contact

• License

• Real example

Features

Dry run mode

Use it. I’m serious. If you don’t and rotate-backups eats more backups than intended you have no right to complain ;-)

Flexible rotation

Rotation with any combination of hourly, daily, weekly, monthly and yearly retention periods.

Fuzzy timestamp matching in filenames

The modification times of the files and/or directories are not relevant. If you speak Python regular expressions, here is how the fuzzy matching works:

# Required components.
(?P<year>\d{4}) \D?
(?P<month>\d{2}) \D?
(?P<day>\d{2}) \D?
(
   # Optional components.
   (?P<hour>\d{2}) \D?
   (?P<minute>\d{2}) \D?
   (?P<second>\d{2})?
)?

All actions are logged

Log messages are saved to the system log (e.g. /var/log/syslog) so you can retrace what happened when something seems to have gone wrong.

Installation

The rotate-backups package is available on PyPI which means installation should be as simple as:

$ pip install rotate-backups

There’s actually a multitude of ways to install Python packages (e.g. the per user site-packages directory, virtual environments or just installing system wide) and I have no intention of getting into that discussion here, so if this intimidates you then read up on your options before returning to these instructions ;-).

Usage

There are two ways to use the rotate-backups package: As the command line program rotate-backups and as a Python API. For details about the Python API please refer to the API documentation available on Read the Docs. The command line interface is described below.

Command line

Usage: rotate-backups [OPTIONS] DIRECTORY..

Supported options:

Option	Description
-H, --hourly=COUNT	Set the number of hourly backups to preserve during rotation: If COUNT is an integer it gives the number of hourly backups to preserve, starting from the most recent hourly backup and counting back in time. You can also pass “always” for COUNT, in this case all hourly backups are preserved. By default no hourly backups are preserved.
-d, --daily=COUNT	Set the number of daily backups to preserve during rotation. Refer to the usage of the -H, --hourly option for details.
-w, --weekly=COUNT	Set the number of weekly backups to preserve during rotation. Refer to the usage of the -H, --hourly option for details.
-m, --monthly=COUNT	Set the number of monthly backups to preserve during rotation. Refer to the usage of the -H, --hourly option for details.
-y, --yearly=COUNT	Set the number of yearly backups to preserve during rotation. Refer to the usage of the -H, --hourly option for details.
-i, --ionice=CLASS	Use the “ionice” program to set the I/O scheduling class and priority of the “rm” invocations used to remove backups. CLASS is expected to be one of the values “idle”, “best-effort” or “realtime”. Refer to the man page of the “ionice” program for details about these values.
-n, --dry-run	Don’t make any changes, just print what would be done. This makes it easy to evaluate the impact of a rotation scheme without losing any backups.
-v, --verbose	Make more noise (increase logging verbosity).
-h, --help	Show this message and exit.

The last section (see below) contains a real example that shows how rotation frequencies can be combined.

Contact

The latest version of rotate-backups is available on PyPI and GitHub. The documentation is hosted on Read the Docs. For bug reports please create an issue on GitHub. If you have questions, suggestions, etc. feel free to send me an e-mail at [e-mail].

License

This software is licensed under the MIT license.

© 2015 Peter Odding.

Real example

Here’s a real world example, more or less. I took a directory of daily backups that had accumulated over a couple of months and cloned the directory structure for testing. The real output is wider because it includes a timestamp and other information, but you get the idea:

$ rotate-backups --hourly=24 --daily=7 --weekly=4 --monthly=12 --yearly=always sample-backups/
INFO Scanning directory for timestamped backups: sample-backups/
INFO Found 266 timestamped backups in sample-backups/.
INFO Preserving sample-backups/2013-10-10@20:07 (matches retention period(s) 'monthly' and 'yearly') ..
INFO Deleting directory sample-backups/2013-10-11@20:06 ..
INFO Deleting directory sample-backups/2013-10-12@20:06 ..
INFO Deleting directory sample-backups/2013-10-13@20:07 ..
INFO Deleting directory sample-backups/2013-10-14@20:06 ..
INFO Deleting directory sample-backups/2013-10-15@20:06 ..
INFO Deleting directory sample-backups/2013-10-16@20:06 ..
INFO Deleting directory sample-backups/2013-10-17@20:07 ..
INFO Deleting directory sample-backups/2013-10-18@20:06 ..
INFO Deleting directory sample-backups/2013-10-19@20:06 ..
INFO Deleting directory sample-backups/2013-10-20@20:05 ..
INFO Deleting directory sample-backups/2013-10-21@20:07 ..
INFO Deleting directory sample-backups/2013-10-22@20:06 ..
INFO Deleting directory sample-backups/2013-10-23@20:06 ..
INFO Deleting directory sample-backups/2013-10-24@20:06 ..
INFO Deleting directory sample-backups/2013-10-25@20:06 ..
INFO Deleting directory sample-backups/2013-10-26@20:06 ..
INFO Deleting directory sample-backups/2013-10-27@20:06 ..
INFO Deleting directory sample-backups/2013-10-28@20:07 ..
INFO Deleting directory sample-backups/2013-10-29@20:06 ..
INFO Deleting directory sample-backups/2013-10-30@20:07 ..
INFO Deleting directory sample-backups/2013-10-31@20:07 ..
INFO Preserving sample-backups/2013-11-01@20:06 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2013-11-02@20:06 ..
INFO Deleting directory sample-backups/2013-11-03@20:05 ..
INFO Deleting directory sample-backups/2013-11-04@20:07 ..
INFO Deleting directory sample-backups/2013-11-05@20:06 ..
INFO Deleting directory sample-backups/2013-11-06@20:07 ..
INFO Deleting directory sample-backups/2013-11-07@20:07 ..
INFO Deleting directory sample-backups/2013-11-08@20:07 ..
INFO Deleting directory sample-backups/2013-11-09@20:06 ..
INFO Deleting directory sample-backups/2013-11-10@20:06 ..
INFO Deleting directory sample-backups/2013-11-11@20:07 ..
INFO Deleting directory sample-backups/2013-11-12@20:06 ..
INFO Deleting directory sample-backups/2013-11-13@20:07 ..
INFO Deleting directory sample-backups/2013-11-14@20:06 ..
INFO Deleting directory sample-backups/2013-11-15@20:07 ..
INFO Deleting directory sample-backups/2013-11-16@20:06 ..
INFO Deleting directory sample-backups/2013-11-17@20:07 ..
INFO Deleting directory sample-backups/2013-11-18@20:07 ..
INFO Deleting directory sample-backups/2013-11-19@20:06 ..
INFO Deleting directory sample-backups/2013-11-20@20:07 ..
INFO Deleting directory sample-backups/2013-11-21@20:06 ..
INFO Deleting directory sample-backups/2013-11-22@20:06 ..
INFO Deleting directory sample-backups/2013-11-23@20:07 ..
INFO Deleting directory sample-backups/2013-11-24@20:06 ..
INFO Deleting directory sample-backups/2013-11-25@20:07 ..
INFO Deleting directory sample-backups/2013-11-26@20:06 ..
INFO Deleting directory sample-backups/2013-11-27@20:07 ..
INFO Deleting directory sample-backups/2013-11-28@20:06 ..
INFO Deleting directory sample-backups/2013-11-29@20:07 ..
INFO Deleting directory sample-backups/2013-11-30@20:06 ..
INFO Preserving sample-backups/2013-12-01@20:07 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2013-12-02@20:06 ..
INFO Deleting directory sample-backups/2013-12-03@20:07 ..
INFO Deleting directory sample-backups/2013-12-04@20:07 ..
INFO Deleting directory sample-backups/2013-12-05@20:06 ..
INFO Deleting directory sample-backups/2013-12-06@20:07 ..
INFO Deleting directory sample-backups/2013-12-07@20:06 ..
INFO Deleting directory sample-backups/2013-12-08@20:06 ..
INFO Deleting directory sample-backups/2013-12-09@20:07 ..
INFO Deleting directory sample-backups/2013-12-10@20:06 ..
INFO Deleting directory sample-backups/2013-12-11@20:07 ..
INFO Deleting directory sample-backups/2013-12-12@20:07 ..
INFO Deleting directory sample-backups/2013-12-13@20:07 ..
INFO Deleting directory sample-backups/2013-12-14@20:06 ..
INFO Deleting directory sample-backups/2013-12-15@20:06 ..
INFO Deleting directory sample-backups/2013-12-16@20:07 ..
INFO Deleting directory sample-backups/2013-12-17@20:06 ..
INFO Deleting directory sample-backups/2013-12-18@20:07 ..
INFO Deleting directory sample-backups/2013-12-19@20:07 ..
INFO Deleting directory sample-backups/2013-12-20@20:08 ..
INFO Deleting directory sample-backups/2013-12-21@20:06 ..
INFO Deleting directory sample-backups/2013-12-22@20:07 ..
INFO Deleting directory sample-backups/2013-12-23@20:08 ..
INFO Deleting directory sample-backups/2013-12-24@20:07 ..
INFO Deleting directory sample-backups/2013-12-25@20:07 ..
INFO Deleting directory sample-backups/2013-12-26@20:06 ..
INFO Deleting directory sample-backups/2013-12-27@20:07 ..
INFO Deleting directory sample-backups/2013-12-28@20:06 ..
INFO Deleting directory sample-backups/2013-12-29@20:07 ..
INFO Deleting directory sample-backups/2013-12-30@20:07 ..
INFO Deleting directory sample-backups/2013-12-31@20:06 ..
INFO Preserving sample-backups/2014-01-01@20:07 (matches retention period(s) 'monthly' and 'yearly') ..
INFO Deleting directory sample-backups/2014-01-02@20:07 ..
INFO Deleting directory sample-backups/2014-01-03@20:08 ..
INFO Deleting directory sample-backups/2014-01-04@20:06 ..
INFO Deleting directory sample-backups/2014-01-05@20:07 ..
INFO Deleting directory sample-backups/2014-01-06@20:07 ..
INFO Deleting directory sample-backups/2014-01-07@20:06 ..
INFO Deleting directory sample-backups/2014-01-08@20:09 ..
INFO Deleting directory sample-backups/2014-01-09@20:07 ..
INFO Deleting directory sample-backups/2014-01-10@20:07 ..
INFO Deleting directory sample-backups/2014-01-11@20:06 ..
INFO Deleting directory sample-backups/2014-01-12@20:07 ..
INFO Deleting directory sample-backups/2014-01-13@20:07 ..
INFO Deleting directory sample-backups/2014-01-14@20:07 ..
INFO Deleting directory sample-backups/2014-01-15@20:06 ..
INFO Deleting directory sample-backups/2014-01-16@20:06 ..
INFO Deleting directory sample-backups/2014-01-17@20:04 ..
INFO Deleting directory sample-backups/2014-01-18@20:02 ..
INFO Deleting directory sample-backups/2014-01-19@20:02 ..
INFO Deleting directory sample-backups/2014-01-20@20:04 ..
INFO Deleting directory sample-backups/2014-01-21@20:04 ..
INFO Deleting directory sample-backups/2014-01-22@20:04 ..
INFO Deleting directory sample-backups/2014-01-23@20:05 ..
INFO Deleting directory sample-backups/2014-01-24@20:08 ..
INFO Deleting directory sample-backups/2014-01-25@20:03 ..
INFO Deleting directory sample-backups/2014-01-26@20:02 ..
INFO Deleting directory sample-backups/2014-01-27@20:08 ..
INFO Deleting directory sample-backups/2014-01-28@20:07 ..
INFO Deleting directory sample-backups/2014-01-29@20:07 ..
INFO Deleting directory sample-backups/2014-01-30@20:08 ..
INFO Deleting directory sample-backups/2014-01-31@20:04 ..
INFO Preserving sample-backups/2014-02-01@20:05 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2014-02-02@20:03 ..
INFO Deleting directory sample-backups/2014-02-03@20:05 ..
INFO Deleting directory sample-backups/2014-02-04@20:06 ..
INFO Deleting directory sample-backups/2014-02-05@20:07 ..
INFO Deleting directory sample-backups/2014-02-06@20:06 ..
INFO Deleting directory sample-backups/2014-02-07@20:05 ..
INFO Deleting directory sample-backups/2014-02-08@20:06 ..
INFO Deleting directory sample-backups/2014-02-09@20:04 ..
INFO Deleting directory sample-backups/2014-02-10@20:07 ..
INFO Deleting directory sample-backups/2014-02-11@20:07 ..
INFO Deleting directory sample-backups/2014-02-12@20:07 ..
INFO Deleting directory sample-backups/2014-02-13@20:06 ..
INFO Deleting directory sample-backups/2014-02-14@20:06 ..
INFO Deleting directory sample-backups/2014-02-15@20:05 ..
INFO Deleting directory sample-backups/2014-02-16@20:04 ..
INFO Deleting directory sample-backups/2014-02-17@20:06 ..
INFO Deleting directory sample-backups/2014-02-18@20:04 ..
INFO Deleting directory sample-backups/2014-02-19@20:08 ..
INFO Deleting directory sample-backups/2014-02-20@20:06 ..
INFO Deleting directory sample-backups/2014-02-21@20:07 ..
INFO Deleting directory sample-backups/2014-02-22@20:05 ..
INFO Deleting directory sample-backups/2014-02-23@20:06 ..
INFO Deleting directory sample-backups/2014-02-24@20:05 ..
INFO Deleting directory sample-backups/2014-02-25@20:06 ..
INFO Deleting directory sample-backups/2014-02-26@20:04 ..
INFO Deleting directory sample-backups/2014-02-27@20:05 ..
INFO Deleting directory sample-backups/2014-02-28@20:03 ..
INFO Preserving sample-backups/2014-03-01@20:04 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2014-03-02@20:01 ..
INFO Deleting directory sample-backups/2014-03-03@20:05 ..
INFO Deleting directory sample-backups/2014-03-04@20:06 ..
INFO Deleting directory sample-backups/2014-03-05@20:05 ..
INFO Deleting directory sample-backups/2014-03-06@20:24 ..
INFO Deleting directory sample-backups/2014-03-07@20:03 ..
INFO Deleting directory sample-backups/2014-03-08@20:04 ..
INFO Deleting directory sample-backups/2014-03-09@20:01 ..
INFO Deleting directory sample-backups/2014-03-10@20:05 ..
INFO Deleting directory sample-backups/2014-03-11@20:05 ..
INFO Deleting directory sample-backups/2014-03-12@20:05 ..
INFO Deleting directory sample-backups/2014-03-13@20:05 ..
INFO Deleting directory sample-backups/2014-03-14@20:04 ..
INFO Deleting directory sample-backups/2014-03-15@20:04 ..
INFO Deleting directory sample-backups/2014-03-16@20:02 ..
INFO Deleting directory sample-backups/2014-03-17@20:04 ..
INFO Deleting directory sample-backups/2014-03-18@20:06 ..
INFO Deleting directory sample-backups/2014-03-19@20:06 ..
INFO Deleting directory sample-backups/2014-03-20@20:06 ..
INFO Deleting directory sample-backups/2014-03-21@20:04 ..
INFO Deleting directory sample-backups/2014-03-22@20:03 ..
INFO Deleting directory sample-backups/2014-03-23@20:01 ..
INFO Deleting directory sample-backups/2014-03-24@20:03 ..
INFO Deleting directory sample-backups/2014-03-25@20:05 ..
INFO Deleting directory sample-backups/2014-03-26@20:03 ..
INFO Deleting directory sample-backups/2014-03-27@20:04 ..
INFO Deleting directory sample-backups/2014-03-28@20:03 ..
INFO Deleting directory sample-backups/2014-03-29@20:03 ..
INFO Deleting directory sample-backups/2014-03-30@20:01 ..
INFO Deleting directory sample-backups/2014-03-31@20:04 ..
INFO Preserving sample-backups/2014-04-01@20:03 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2014-04-02@20:05 ..
INFO Deleting directory sample-backups/2014-04-03@20:03 ..
INFO Deleting directory sample-backups/2014-04-04@20:04 ..
INFO Deleting directory sample-backups/2014-04-05@20:02 ..
INFO Deleting directory sample-backups/2014-04-06@20:02 ..
INFO Deleting directory sample-backups/2014-04-07@20:02 ..
INFO Deleting directory sample-backups/2014-04-08@20:04 ..
INFO Deleting directory sample-backups/2014-04-09@20:04 ..
INFO Deleting directory sample-backups/2014-04-10@20:04 ..
INFO Deleting directory sample-backups/2014-04-11@20:04 ..
INFO Deleting directory sample-backups/2014-04-12@20:03 ..
INFO Deleting directory sample-backups/2014-04-13@20:01 ..
INFO Deleting directory sample-backups/2014-04-14@20:05 ..
INFO Deleting directory sample-backups/2014-04-15@20:05 ..
INFO Deleting directory sample-backups/2014-04-16@20:06 ..
INFO Deleting directory sample-backups/2014-04-17@20:05 ..
INFO Deleting directory sample-backups/2014-04-18@20:06 ..
INFO Deleting directory sample-backups/2014-04-19@20:02 ..
INFO Deleting directory sample-backups/2014-04-20@20:01 ..
INFO Deleting directory sample-backups/2014-04-21@20:01 ..
INFO Deleting directory sample-backups/2014-04-22@20:06 ..
INFO Deleting directory sample-backups/2014-04-23@20:06 ..
INFO Deleting directory sample-backups/2014-04-24@20:05 ..
INFO Deleting directory sample-backups/2014-04-25@20:04 ..
INFO Deleting directory sample-backups/2014-04-26@20:02 ..
INFO Deleting directory sample-backups/2014-04-27@20:02 ..
INFO Deleting directory sample-backups/2014-04-28@20:05 ..
INFO Deleting directory sample-backups/2014-04-29@20:05 ..
INFO Deleting directory sample-backups/2014-04-30@20:05 ..
INFO Preserving sample-backups/2014-05-01@20:06 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2014-05-02@20:05 ..
INFO Deleting directory sample-backups/2014-05-03@20:03 ..
INFO Deleting directory sample-backups/2014-05-04@20:01 ..
INFO Deleting directory sample-backups/2014-05-05@20:06 ..
INFO Deleting directory sample-backups/2014-05-06@20:06 ..
INFO Deleting directory sample-backups/2014-05-07@20:05 ..
INFO Deleting directory sample-backups/2014-05-08@20:03 ..
INFO Deleting directory sample-backups/2014-05-09@20:01 ..
INFO Deleting directory sample-backups/2014-05-10@20:01 ..
INFO Deleting directory sample-backups/2014-05-11@20:01 ..
INFO Deleting directory sample-backups/2014-05-12@20:05 ..
INFO Deleting directory sample-backups/2014-05-13@20:06 ..
INFO Deleting directory sample-backups/2014-05-14@20:04 ..
INFO Deleting directory sample-backups/2014-05-15@20:06 ..
INFO Deleting directory sample-backups/2014-05-16@20:05 ..
INFO Deleting directory sample-backups/2014-05-17@20:02 ..
INFO Deleting directory sample-backups/2014-05-18@20:01 ..
INFO Deleting directory sample-backups/2014-05-19@20:02 ..
INFO Deleting directory sample-backups/2014-05-20@20:04 ..
INFO Deleting directory sample-backups/2014-05-21@20:03 ..
INFO Deleting directory sample-backups/2014-05-22@20:02 ..
INFO Deleting directory sample-backups/2014-05-23@20:02 ..
INFO Deleting directory sample-backups/2014-05-24@20:01 ..
INFO Deleting directory sample-backups/2014-05-25@20:01 ..
INFO Deleting directory sample-backups/2014-05-26@20:05 ..
INFO Deleting directory sample-backups/2014-05-27@20:03 ..
INFO Deleting directory sample-backups/2014-05-28@20:03 ..
INFO Deleting directory sample-backups/2014-05-29@20:01 ..
INFO Deleting directory sample-backups/2014-05-30@20:02 ..
INFO Deleting directory sample-backups/2014-05-31@20:02 ..
INFO Preserving sample-backups/2014-06-01@20:01 (matches retention period(s) 'monthly') ..
INFO Deleting directory sample-backups/2014-06-02@20:05 ..
INFO Deleting directory sample-backups/2014-06-03@20:02 ..
INFO Deleting directory sample-backups/2014-06-04@20:03 ..
INFO Deleting directory sample-backups/2014-06-05@20:03 ..
INFO Deleting directory sample-backups/2014-06-06@20:02 ..
INFO Deleting directory sample-backups/2014-06-07@20:01 ..
INFO Deleting directory sample-backups/2014-06-08@20:01 ..
INFO Preserving sample-backups/2014-06-09@20:01 (matches retention period(s) 'weekly') ..
INFO Deleting directory sample-backups/2014-06-10@20:02 ..
INFO Deleting directory sample-backups/2014-06-11@20:02 ..
INFO Deleting directory sample-backups/2014-06-12@20:03 ..
INFO Deleting directory sample-backups/2014-06-13@20:05 ..
INFO Deleting directory sample-backups/2014-06-14@20:01 ..
INFO Deleting directory sample-backups/2014-06-15@20:01 ..
INFO Preserving sample-backups/2014-06-16@20:02 (matches retention period(s) 'weekly') ..
INFO Deleting directory sample-backups/2014-06-17@20:01 ..
INFO Deleting directory sample-backups/2014-06-18@20:01 ..
INFO Deleting directory sample-backups/2014-06-19@20:04 ..
INFO Deleting directory sample-backups/2014-06-20@20:02 ..
INFO Deleting directory sample-backups/2014-06-21@20:02 ..
INFO Deleting directory sample-backups/2014-06-22@20:01 ..
INFO Preserving sample-backups/2014-06-23@20:04 (matches retention period(s) 'weekly') ..
INFO Deleting directory sample-backups/2014-06-24@20:06 ..
INFO Deleting directory sample-backups/2014-06-25@20:03 ..
INFO Preserving sample-backups/2014-06-26@20:04 (matches retention period(s) 'daily') ..
INFO Preserving sample-backups/2014-06-27@20:02 (matches retention period(s) 'daily') ..
INFO Preserving sample-backups/2014-06-28@20:02 (matches retention period(s) 'daily') ..
INFO Preserving sample-backups/2014-06-29@20:01 (matches retention period(s) 'daily') ..
INFO Preserving sample-backups/2014-06-30@20:03 (matches retention period(s) 'daily' and 'weekly') ..
INFO Preserving sample-backups/2014-07-01@20:02 (matches retention period(s) 'daily' and 'monthly') ..
INFO Preserving sample-backups/2014-07-02@20:03 (matches retention period(s) 'hourly' and 'daily') ..