A backup server isn't much help if two machines start changing the same files.

Flux's October 19 FluxOS 8.21 update tackles that problem: one primary writes, standby copies stay read-only, and a primary shutting down passes along its final writes.

For $FLUX watchers, this is the quieter side of decentralized cloud: keeping an app's data consistent when servers change roles. I'd still want backups of important data; a cleaner handover isn't protection against every kind of failure.