I've been trying to use a raspberry pi as my backup disk for years and never had any success.
I need to preface this and say that i back up a lot of data, i use it for all my photography and digital art etc, so a few terabytes of data in hundreds of thousands of files.
At every install the sync would install and work great until i reach some threshold of number of files at which point it would stall. This stalling would not be very noticeable, for example it would just pause. The in-browser resylio window would just keep displaying the same thing, one folder is in the middle of sync, and a few are being scanned. So i would leave it there for a few weeks to see if anything would move and nothing. no matter how many times I restart and check things it just would not move forwards.
recently i had luck with the raspberry pi OS, but not its hardware in that I installed the OS on a normal (but old) computer and its now working fine.
So TL:DR, i think the raspberry pi hardware just cant handle the load or resilio with more then a few thousand files.
