3 2 1 Backups
Backups are about
keeping copies of data so you can resore in the event of deletion or corruption, or to go back to an earlier point in time.
3-2-1 is the now time worn advice of:
- RAID is not backup it is hard disk redundancy. The data copies are not independent, if one goes they all go.
- Whatever it is it will fail, sooner or later, and at a time most inconvenient to you.