Bash script for backup based on rsync with deleted file archive and auto-delete functionality

Note: This script hasn't been tested extensively and it's not that good at making sure nothing gets accidentally deleted. So use this at your own risk. If you find any bug, feel free to open an issue.

First of all make sure you have jq and rsync installed. Everything else should be pre-installed on any modern linux system. Then download the script and read the comments in order to modify it to your likings. To automate this you can use systemd timers.

This script is an rsync wrapper with support for deleted file archive and auto-delete. It basically makes a backup from a (your PC) to b (your backup) and then checks if files deleted from a are still on b. Said files will be moved into a pre-determined archive directory and be auto-deleted after a certain amount of days after they were deleted (which you can configure).

Back when I had Windows, I used to have bvckup2 for my backups. This had an option to archive deleted files on a specific directory and then auto-delete them after a certain amount of days. I searched really deep for something like this but the closest thing I got was snapshot rsync apps (like rsnapshot) which create a mess on the backup (I don't want multiple versions of a file, one is fine for me). So I just made this; a simple script which does exactly that, based on rsync.

This app works by first making a normal copy with rsync and then doing a dry run of rsync --delete. Then it parses all the files rsync thinks need to be deleted, moves them into an archive folder and saves them in a "database" to delete in a feature date. For more info on how it works, see the comments inside the script.

MIT License
Copyright (c) 2022 Nikolas Spiridakis

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