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tradersam

Alternatively: "Hard-drives let you permanently keep your stuff, for life"

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Hard drives are an especially bad choice for lifetime reasons, and SSDs don't solve the problem either :P

Tape is usually the preferred magnetic media for long-term storage.

I don't agree — that's why things like redundancy are commonplace. :D

“You're weak on logic, that's the trouble with you. You're like the guy in the story who was caught in a sudden shower and Who ran to a grove of trees and got under one. He wasn't worried, you see, because he figured when one tree got wet through, he would just get under another one."

http://multivax.com/last_question.html

Huh, I don't think I've seen a reference to that story in years, but just emailed it to a coworker a couple hours ago.

One of my all time favorites. Though it took me a while to remember the source of the quote. I thought it had been used in the context of global warming so google didn’t turn up much. Then I remembered it’s actually from a story about universal cooling.

That's not a hard drive. That's a system built on top of hard drives.

And so is perkeep.

That's incorrect. RAID is a system build on top of hard drives for redundancy. Redundancy (for this use of the word) is simply duplication across multiple hard-drives, which doesn't require a system at all.

Really, this is a very simplistic view of long term storage.

A RAID is not magically more reliable than a single drive, it needs a bunch of infrastructure and it needs to be duplicated to some other location far away enough to ensure that a single catastrophe such as a fire does not destroy your entire raid.

You are missing the wood for the trees: hard drives and raid devices are storage mechanisms that fall far short of the boundary conditions set to keep something permanently, at worst you will store your data for a couple of hour like that and in ideal conditions maybe for a couple of years, but on a scale of decades or centuries they are useless as a complete solution, though they could be part of such a solution.

I wonder how terrifying it would be to get a notification every time a single underlying storage device on something like Dropbox or S3 failed. We all know there is some kind of redundant system but how often does your data get moved around because of failures?

At that scale it's probably like a slow rain.

You could be made to feel better if the alert only came when it concerned your data. But even then, and going by the NAS sitting under my desk you could be months without any activity and then suddenly two drives fail in two weeks. It's a nice little random data generator.

Ah yeah I was unclear there, I meant notifications of the devices under your own data.

e: Also, is it so surprising that your drives failed around the same time? It’s likely they were purchased together!

Past a certain point it would be just a part of the job. As long as you have hot spares, you'd just go around replacing failed drives every day or whenever.

Just saying to yourself "I save all my stuff on two drives" is a system. It's just kind of a crappy one that's really prone to failure.

redundancy is not helpful if your system consistently fails after some regular interval

Check out M-DISC https://en.wikipedia.org/wiki/M-DISC

It's not clear how much better than they are than regular media since there haven't been many tests. There are two that I'm aware of, one by the French Archives (who've done this a few times it so happens) and one by the US DoD.

The French found that M-DISC didn't perform much better than regular DVDs and that a weird kind of glass DVD beat everything else hands down.

The Americans found no errors at all in their tests of M-DISC while all other disks encountered them.

I suspect the important differences were:

- The Americans' tested the discs after light exposure, the French did not. It may be that the light caused the regular DVDs to fail but not the M-DISC.

- The French tests were far longer (1000h) than the Americans' (24h). It may be that M-DISC can't survive the adverse conditions past a certain point that the Americans didn't reach.

Also as far as I'm aware, there are no tests of the Blu-Ray variant of M-DISC.

Personally, given the cost of M-DISC, I'd buy a few cheap terrible Blu-Rays instead and just make sure they're not exposed to too much light.

French test: https://documents.lne.fr/publications/guides-documents-techn...

American: http://www.esystor.com/images/China_Lake_Full_Report.pdf

> While the exact properties of M-DISC are a trade secret

If long-term accessibility is the goal, not off to a good start...

They can be read with any standard DVD or Blu-ray drive. Not that anyone has one of those any more.

Spent the whole morning burning them, as it so happens.

Trying to get data in to an air-gapped environment is a true PITA.

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