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Comment by LinuxBender | Hacker News Reader

As others have mentioned, use encryption. But that has gaps as someone can hold onto the drive and wait for impossible to break to become somewhat expensive to break to broke by mistake through bad encryption implementation.

Put the encrypted drive into a hydraulic press and flatten it into a thin sheet, then run that sheet through a chop saw, or just use tin-snips if your hydraulic press was powerful enough. A hydraulic press and a chop saw are a few hundred bucks whereas drive shredders can range from $30k to $200k.

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Delete all the files then "dd" from the random device until the drive is full? Must we always jump straight to the hydraulic press?

As mentioned in the article, that's not reliable. Drives have lots of overprovision blocks and there's no way of consistently forcing them to be used; and drives might mark blocks as too questionable/worn to reuse and never reset them.

Also a standard failure mode of SSDs is refusing to accept writes, so you'll have to handle that case.

Encryption plus a single rewrite is likely many times more sufficient than ever needed.

Even if there is a massive 10% block reserve, you looking at a random 10% of an entire encrypted drive.

Figuring out how to just decrypt those blocks is a very hard challenge, then figuring out the SSD block mapping is going to be very challenging, and then for a chance to maybe get something valuable from that 10%.

Multiple very difficult challenges for only a chance of maybe recovering something useful.

Related, I just had a hard drive head crash. I was able to use dd_rescue to read out 40% of the drive before it fully gave out. It's amazing, but at least NTFS stores data everywhere. I recovered a few small plain text file, but not a single image was recoverable. It was pretty shocking to me.

Must we always jump straight to the hydraulic press?

Not always. I suppose it depends on your information security case. If your goal is to secure your kids laptop from the average thief that is heading to the pawn shop, maybe "secure erase" of encrypted drives may be sufficient.

If on the other hand one is protecting intellectual property, customer data and so on, then perhaps that average thief was hired by someone with significant resources. I would wager that a percentage of the people reading this comment are using a work laptop and have some IP on their drive that in the wrong hands could cost billions. Even some of the emails I've seen could do significant damages.

> the random device

/dev/zero would be sufficient.

Also easier to confirm things worked (if desired) since you know what to expect on read-back.

You're assuming the drive doesn't do something smart when it detects it's being filled with zeroes. It could at least in theory decide to do the same thing it does when you TRIM a sector.

I suspect it won’t be long (if it isn’t already the case) that defacto run-length encoding is built into SSD firmware.

Write 5 gig of zeros? OK! You just got more drive reserve capacity!

Hydraulic press is too obscure, .45 ACP works just as well.

But it depends on your risk profile, for most people a wipe-and-reuse is going to be fine, especially if the "reuser" is already a trusted entity.

A firearm is a silly tool for this. A hammer (optionally combined with good nails) can do substantially the same thing to all relevant materials (aluminum, glass, ceramic, silicon, plastic), but cheaper and more safely.

I think a springloaded center punch to each of the chips would do a pretty good job of it.

https://www.harborfreight.com/spring-loaded-center-punch-621...

Silly? Maybe. Fun? You bet!

I suppose if one could obliterate most of the chips with 3 or 4 well placed shots then your solution is certainly more cost effective than mine should one not have a future use for a press. This sounds like a video idea for DemolitionRanch.

I guess used microwave would be easiest and cheapest option for SSDs

A microwave may not even damage the chips internals; you'd have to actually test and verify it.

That's a nice solution in the US I guess, not so much for us in Europe :)

I think an angle grinder would be more accessible than a press.

Open them, heat treat the disks in a bonfire, use the magnets as fridge magnets (those are quite strong, can fix entire books to the fridge instead of just notes).

Last I checked, SSDs don't have those (see thread title).

This is a much more expensive and less effective solution than a coffee tin and some gasoline.

> ...hydraulic press was powerful enough.

Can we repurpose a die press to this task and if so, would a 100 ton AvE die press [1] be powerful enough?

[1] https://www.youtube.com/watch?v=d_LSPX8cNaE

I suppose provided that we are not punching and instead crushing the SSD chips to dust that would work. Punching holes would leave some chips.

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