Yikes! How to properly apply a 3-2-1 Backup Strategy
Posted: 13-Feb-2023
The classic 3-2-1 Backup Strategy (have 3 copies across 2 different media types with 1 off-site) needs a bit of clarification when using a NAS. Copies and different media shared inside the NAS leave you vulnerable to NAS failure - that's pretty obvious, but the solution cannot rely on a backup disk attached inside the NAS, you must use at least an external USB device attached to the NAS (if not something connected via a network). Read all the gory detail in this article. Long story short - “A single disk in a Synology box (connected via SATA internally) can never be read outside a Synology box … doesn’t matter if it’s JBOD, Basic, SHR, RAID… doesn’t matter if it’s formatted BTRFS or ext4."