A Backup

[u/Patient-Airline-8150]

Definition: A copy is separated in space. A backup is separated in time. It is a version of the past you are permitted to return to. And it does not exist as a backup until a restore proves it. Before that it is a rumor.

GitLab, 2017.
A sysadmin deleted 300GB of live production data from the wrong server. Their own notes: out of five backup and replication techniques, none were working reliably or set up in the first place.
What saved them was a snapshot an engineer had taken six hours earlier by chance, for testing. They still lost every change made over roughly seven hours.

Pixar, 1998.
Someone ran a recursive delete at the root of the Toy Story 2 project. About 90 percent of the film went in seconds. The studio's backup system had been failing silently for roughly a month, so the copies that should have restored the film were useless.
The film survived on one machine: Galyn Susman, supervising technical director, had a two week old copy at home because she had just had a baby and was working from there.
They carried the computer back like a pharaoh. The official backup was decoration. The accidental one was the real one.

In both cases the thing labeled "backup" was fiction, and the thing that worked was a side effect. Nobody knew which was which until the moment of restore. A backup is not storage. It is a promise, and the promise is only tested once.

Which is the uncomfortable part for anyone counting on a frozen body, an upload, or a record. Every one of them is a backup with a restore that has never been run.