This guide aims to take a look at a distributed, scalable SeaweedFS as a backend storage for an OwnCloud server. Why not NextCloud? Because NextCloud's S3 connector is outdated and not maintained, and won't work with SeaweedFS. Both OwnCloud and NextCloud have the same support and the same plugins. The only concern anyone has is some weird split that happened between the two years ago. It's fine.
This was a giant pain in the ass, but eventually I got it working. This is how.
All servers start from fresh, clean installs of Ubuntu 18.04.3
This guide will use three seperate boxes (one master/OwnCloud and two slaves). I'm assuming there's spare, unformatted disks attached to the slaves. If not, ignore or change the section on mounting to fit your needs.