Maybe you have an agreement with another friend and a set of scripts that do this.
Maybe you're using some kind of decentralized backup system where you have a big blob of encrypted, de-duplicated Other People's Backups in exchange for all your stuff being treated the same.
Or maybe you just don't provide all of this, maybe the entire network expects your server to be fragile and is running everything in a virtual machine to start with. You just have a box in the closet that runs a node in the mesh, with however much power and storage you want to throw at it, and this grants you x% of those numbers from ClosetMesh. It's pretty cheap and easy to have enough ClosetMesh storage to do something useful in a box about the size of the one your phone came in.
There is probably at least one SF novel's worth of backstory between where we are now and the world where everything runs on top of ClosetMesh. Do you want to be part of it? There's a bunch of projects trying to make this sort of thing work.
I just wanna have physical ownership of the photos I upload into the cloud
if my shit goes down, only me is to blame and only me has a problem
if my house get's blown over by a river, I have bigger problems than streaming music from my own personal server and backing up my own photos
in a more ideal world, I have some replication on 'friends' servers. but nobody runs their own shit.
Bittorrent-like tech has answers for you here.