External storage / primary storage (openstack)

So my problem is that i need openstack for my storage solution, but i simply have no idea what to make for nextcloud to work with openstack object storage, or how I even set the right version of openstack up.

So the reason why I need openstack, is that I want to make 3 openstack servers synchronize data with eacother, so that if server 1 goes down, server 2 will still have the data stored in its own seperate bracket of some sort.

I know its a lot to ask for, but im open for anything.