automate off-disk backups for a wiki using Mediawiki/MariaDB on Ubunto 20.4

We have off-disk file space and some scripts for making backups. I need someone to test the scripts to make sure they are working, and then also, automate moving the backups from the main disk to the off-system disk (set up a file mount?). Finally, I need automation to prune the off-disk backups so the disk doesn't fill up (or else, a process/schedule for doing so manually). Must be familiar with MySQL, Mediawiki and Ubuntu command line.