DarthRUSerious

Another option is SyncThing. You can install the unraid docker and then the community app on Package Manager. it's a little tricky to get the paths correct, but after that, it works fine. You can also install the Container Manager that will allow you to install any number of Docker containers, like UrBackup or LuckyBackup To be clear, these are sync'd mirrors, not true backup solutions like snapshots. Borg, Duplicacy and others provide options for actual immutable snapshots.