I've seen painful situations in Cluses: 15 years of photos lost, an SME's accounting gone, a PhD thesis vanished. All preventable with the 3-2-1 rule.
The rule in one sentence
- 3 copies of your files
- On 2 different media
- Including 1 off-site (away from home)
Concrete example for a Cluses family
Family photos (30 GB)
- Copy 1: your PC
- Copy 2: USB external drive 1 TB (€50) — auto-sync with FreeFileSync or Time Machine on Mac
- Copy 3: encrypted cloud — Google Photos (199GB at €2.99/month) or OneDrive (100GB at €1.99/month)
Total: €50 drive + €2-3/month cloud.
For pros: 3-2-1-1-0
For an Arve Valley SME, I recommend the extended version: 3 copies, 2 media, 1 off-site, 1 immutable (cloud with versioning, ransomware-proof), 0 errors verified monthly.
Common mistakes
"I have my photos on OneDrive, it's backed up"
No. OneDrive is sync, not backup. Delete a file = it's deleted in the cloud too. Ransomware encrypts = OneDrive too.
"My external drive is always plugged in"
Then ransomware encrypts it too. Plug only for backup, then unplug.
"I back up once a year"
Match backup frequency to creation frequency: photos monthly, pro docs weekly, accounting daily auto.
My setup in Cluses
€50 backup setup plan (on-site or remote): hardware choice, auto-sync, restore test, 30-min training. Call +33 7 83 44 65 99.