Most businesses find out their backups do not work on the day they need them. The job ran every night, the dashboard was green, and the file that comes back is empty, corrupt, or three months stale.
A green tick is not evidence
A backup job reports that it finished. It does not report that the data inside it is usable, that the database was quiesced before the snapshot, or that anyone still has the key needed to decrypt it. Those are different questions, and the only way to answer them is to restore something.
The three failures we see most often, in order:
- The backup captured the files but not the database, so the application comes back without its data.
- Retention quietly shortened after a storage change, so the oldest copy is days old rather than months.
- Nobody currently employed has the credentials to read the archive.
What we do instead
Once a quarter we restore a real system from a real backup into an isolated environment, and check that it starts and that the data is current. It takes an afternoon. You get the written result either way, including the times it did not work, because that is the result worth having.
If you cannot name the date of your last successful restore, you do not have a backup. You have a job that finishes.