Yes, the dreaded fiber vs. backhoe. But if your distributed file system is geographically redundant, you're not exposed to that, at least from an integrity POV. It sucks that 1/3 or 1/5 or whatever of your serving fleet just disappeared, but backup won't help with that.

> But if your distributed file system is geographically redundant

Redundancy and backups are not the same thing! There's some overlap, but treating them as interchangeable will occasionally result in terrible outcomes, like when a config change that results in all 5/5 datacenters fragmenting and failing to create a quorum, then finding out your services have circular dependencies when you are trying to bootstrap foundational services. Local backups would solve this, each DC would load last known good config, but rebuilding consensus necessary for redundancy requires coordination from now-unreachable hosts.