The 3-2-1 rule is the easiest way to remember what a real backup looks like: keep three copies of your data, on two different types of media, with one copy offsite.
Applying it to a NAS
- Copy 1: the original data on your computers and phones
- Copy 2: the NAS, which gives you a second copy on different hardware
- Copy 3: an offsite copy, such as encrypted cloud backup or a drive stored at another location
Use snapshots against mistakes and ransomware
Most NAS systems can take scheduled snapshots, which are point-in-time versions of your files. They let you roll back an accidental delete or an encrypted share, as long as the snapshots themselves are protected from the machines that could be infected.
Automate and test
Schedule backups so you never rely on memory, and set up alerts for failures. Then actually restore a few files every few months. A backup you have never restored is only a hope.
Rule of thumbIf losing the NAS, and the room it sits in, would be a disaster, you are missing the offsite copy. New to the topic? Start with what is a NAS.
