Backup
Well, disks might crash sometimes
We can protect data by backing it up to another storage device.
Tape is a very cost effective method to store data that does not need to be accessed online.
A typical backup schedule:
- Day 1: Complete backup
- Day 2: Increment from day 1.
- Day 3: Increment from day 2.
- …
- Day n: Increment from day n-1.
- Go back to day 1.