The 3-2-1 backup rule
The difference between a scare and a catastrophe is almost always a backup that actually existed.
Almost everyone "does backups". Few test them. And a backup you never restore isn't a backup: it's a hope.
The 3-2-1 rule
- 3 copies of your data.
- On 2 different media.
- 1 of them offsite.
Why each number matters
- 3 copies because the primary can fail at the same time as a replica.
- 2 media because a failure of one disk type won't take out both.
- 1 offsite because a fire, a theft, or ransomware encrypting the network must not reach your last copy.
What almost nobody does
Test the restore. Schedule a real test every so often: restore a file, a database, a machine. If you don't test it, you don't know whether you have backups or a placebo.
#backups#recovery#continuity