srnjak / purge-backups

A simple bash script to manage backups based on a retention policy.

Backup retention policy script

purge-backups is a Bash script for deleting old backups based on a retention policy.

Usage

purge-backups -p <path> -x <prefix> [-d <days>] [-w <weeks>] [-m <months>] [-y <years>] [--dry-run]
purge-backups -h

Options

Option	Description	Default Value
-p, --backup-path <PATH>	The path to the directory containing the backup directories.
-x, --backup-prefix <PATH>	Prefix of the backed up entity (e.g., my_backup).
-d, --daily-retention <DAILY>	Retention period for daily backups in days.	7d
-w, --weekly-retention <WEEKLY>	Retention period for weekly backups in weeks.	4w
-m, --monthly-retention <MONTHLY>	Retention period for monthly backups in months.	12m
-y, --yearly-retention <YEARLY>	Retention period for yearly backups in years.	2y
--dry-run	Show which backups would be deleted without actually deleting them.
-h, --help	Show help message.

Note that when specifying the retention period using the -d, -w, -m, or -y options, you must include a unit of time (d for days, w for weeks, m for months, or y for years). If no unit is specified, the script will default to days.

Retention Policy

The retention policy is to keep daily backups for a specified number of days, weekly backups for a specified number of weeks, monthly backups for a specified number of months, and yearly backups for a specified number of years. The retention periods are set using the options described above.

Requirements

Backup directory name format is important for efficient management and organization of backup files. In some cases, backup directories need to be pruned based on their name. Therefore, it is essential to follow a specific naming convention to ensure that the backup files are correctly identified and retained. The following is a backup directory name format that can be used for various backup types:

<prefix>_<date>_<time>_<suffix>

• prefix: the name of the backed up entity (e.g., database name).
• date: the date when the backup was taken in the format yyyy-MM-dd.
• time: the time when the backup was taken in the format hhmmss.
• suffix: the retention type, either daily, weekly, monthly, or yearly.
  • Daily backups: suffix is 'daily'.
  • Weekly backups: suffix is 'weekly'.
  • Monthly backups: suffix is 'monthly'.
  • Yearly backups: suffix is 'yearly'.

Examples

Retention policy: keep daily backups for 30 days

purge-backups -p /backups/mybackup -x my_backup -d 30d

Retention policy: keep monthly backups for 6 months and weekly backups for 4 weeks, and daily backups for 3 days

purge-backups -p /backups/mybackup -x my_backup -m 6M -w 4W -d 3D

Perform a dry run to print the directories that would be deleted without actually deleting them

purge-backups -p /backups/mybackup -x my_backup --dry-run

The scheduler script

The purge-backups-scheduler script is designed to automate the process of purging old backups based on a set of retention periods. It reads configuration files from a specified directory, extracts the backup path, backup prefix, and retention periods from each file, and then calls the purge-backups command with the extracted parameters.

More information on how to use the purge-backups-scheduler script can be found here.

License

This project is licensed under the MIT License - see the LICENSE file for details.

purge-backups's Issues

Backup prefix option

There should be a new option in the script which will define backup prefix.

Aggregation script

Create an aggregation script which will read configuration files and call purge-backups script per each.
This script should be added to daily cron.

Manage cronjob when updating package

Cronjob disapeared when package was upgraded to newer version.

Purge time not calculated correctly

If I set purge time i.e. for 1 day, the script deletes backup directory which is younger than a day as well.

Purging should be applied to directories with specified prefix only

There might be multiple different backups (with different directory prefixes) under the same path.
Purging should take into consideration those with the specified prefix only.

Purge scheduler config should work even if not executable