Backups: the 3-2-1 rule
Use the 3-2-1 rule to make sure no single theft, breakdown or ransomware attack can take your photos and documents, and learn why sync alone isn't a backup.
WHAT TAKES YOUR DATA
Five ways files disappear
Loss or theft, breakage, ransomware or other malware, being locked out of an account, and plain human mistakes like deleting the wrong folder. A good backup plan answers all five, not just the one you're thinking about today.
A copy on a USB stick in the same bag as your laptop survives a broken screen. It doesn't survive the bag being stolen.
The 3-2-1 rule
Keep 3 copies of anything you can't replace (the original plus two backups), on 2 different kinds of storage (say, your phone and an external drive), with 1 copy somewhere else: in the cloud or at another address. No single accident then reaches every copy.
Photos on your phone, a monthly copy on an external drive at home, and a second drive you keep at your parents' house. Three copies, two kinds, one away.
Check yourself
Shadi keeps her photos on her phone and copies them every month to a USB stick that lives in her handbag, next to the phone. Measured against 3-2-1, what is she missing most?
- Nothing: two copies on two kinds of storage is already enough
- A faster USB stick, so the monthly copy takes less time
- A copy kept somewhere else, since one stolen bag takes both
- Photos belong only in the cloud, because USB sticks fail too easily
Show the answer
A copy kept somewhere else, since one stolen bag takes both
Right. Her two copies travel together, so one theft or one spilled drink can take both. A copy at home, with family or in the cloud fixes that.
Sync is not the same as backup
Sync
Keeps two places identical. Delete a file on your phone and it's deleted in the cloud too. If ransomware scrambles your files, the scrambled versions can sync as well. Some services keep a trash or older versions for a limited time, which helps if you notice quickly.
Backup
A separate copy from a point in time that you can go back to. Changes on your phone don't reach it until the next backup, and good backup tools keep several older versions.
Check yourself
Daniel's documents folder syncs to a cloud service automatically. That alone means ransomware on his laptop can't cost him his files.
Show the answer
False
False. Sync copies changes, and encrypted files are changes. His cloud copy may fill with the same scrambled files. Version history might rescue him if the service keeps it long enough, but an offline backup is what makes sure.
A backup plan in one afternoon
- List what you can't replace
Photos and videos, documents and scans, contacts, important chats, and your two-step login recovery codes.
- Turn on automatic phone backup
To a cloud service or to your computer, whichever works reliably where you live. Automatic beats good intentions.
- Add a monthly offline copy
Copy everything to an external drive, then unplug it. Put a reminder in your calendar.
- Keep one copy away from home
A cloud copy, or a second drive at a relative's home that you swap now and then.
- Test a restore
Pick a few files and actually open them from the backup. Do it again every few months.
Check yourself
Match each disaster to the copy that saves you
Show the answer
- Your phone is stolen on the metro → The automatic backup to the cloud or your computer
- Ransomware locks your laptop → The external drive that was unplugged
- You deleted a folder by mistake last month → A backup that keeps older versions
- A pipe bursts and floods your home → The copy kept at another address
BACK UP THE KEYS
Your backup plan includes your logins
Losing your phone can also mean losing your authenticator app. Keep your recovery codes printed or in your password manager, and check whether your authenticator app can back up or transfer its codes. And protect the backup itself: a backup drive holds a copy of everything, so give it a password or encryption if it supports it.
A drive with ten years of photos and scans of your ID, left unencrypted in a drawer, is a gift to whoever finds it.
Check yourself
Kourosh is moving to a new phone. His authenticator app on the old phone holds the codes for his email and his bank. What should he do before he wipes the old phone?
- Nothing special: the codes move with his SIM card
- Wipe it first, then set up the authenticator again from scratch on the new one
- Move the codes to the new phone and check each login works
- Keep the old phone in a drawer forever, just in case
Show the answer
Move the codes to the new phone and check each login works
Right. Only wipe the old phone once every account opens with the new one, and keep his recovery codes somewhere safe in case one doesn't.
Lesson recap
- 3-2-1: three copies, on two kinds of storage, one of them somewhere else.
- Sync keeps things identical, mistakes and ransomware included. A backup lets you go back.
- Keep one copy offline: back up, then unplug.
- Back up your recovery codes too, and test a restore every few months.