yep, in my observation the ratio of "having backup processes" to "having periodic disaster recovery drill" is somewhere in the area of 20:1.

Even within the same company. Every division has backup processes, only few actually try to recover the data once in a while...

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bluGill 2 hours ago | parent [-]

At least they have a process. That gives you a chance. Often the process itself is good - you didn't test it but the vendors all did and so the data is there - it might be hard to restore, but it can be done by experts after the fact. The drill means you can recover in a "short time" instead of a "long time" (short time can range from minutes to days, while long time days to years)

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rickdeckard 2 hours ago | parent [-]

yes and no.

I've ran drills with companies which concluded that the incremental backups couldn't be restored due to some data corruption issue (no readback test was ever done).

Luckily the company also did a full backup every 6 months, so a disaster would have only thrown them back 6 months at max! /s ;)

But yes, some issues were even more simple: I had a case where performing a restore required twice the storage size of the uncompressed data, and the company actually didn't have the infrastructure ready to do that in case of a disaster...

	▲	bluGill 2 hours ago \| parent [-]
		I'll bet that if it really was important you could pay someone (LLMs make this easier) to dig through the data byte by byte and get everything back despite the corruption. It would take years, and be very expensive, but typically there is enough redundancy to figure it out. Often you only really need a small subset of the data and can live without the rest. Don't get me wrong, drills are important! You should do them. However backups without a restore drill better than no backups at all. Even if you only get the last full backup, the data from the last 6 months will be the easiest to recreate from scratch if you must.