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[SOLVED] How Many Times Needed to Securely Erase An HDD?

System32_76

Commendable
Jul 29, 2019
110
2
1,585
The title explains itself.

I'm using Darik's Boot and Nuke to securely erase an HDD.

I'm using the RCMP option, which involves 8 passes, and it seems good enough for that.
I also saw an option called Gutmann Wipe, which involves 35 passes, but it seems overkill.
 
Is this drive to be sold?
If so, one pass with DBAN is good.

If to keep for your future use, one pass with DBAN is overkill.

If you are the target of the NSA/FBI/GCHQ....physical destruction is the only solution.
It's to create a generalized system image on Windows with Sysprep. I want to make sure the image I create doesn't contain any previous users' data. That would be bad.
 
That is an old concept, made for when drives were much smaller.
Doing that on any reasonable size drive today would take a week. Literally.

It is absolutely not needed.

I see. This article proves what you said. So it was needed for older HDD tech.
 
The title explains itself.

I'm using Darik's Boot and Nuke to securely erase an HDD.

I'm using the RCMP option, which involves 8 passes, and it seems good enough for that.
I also saw an option called Gutmann Wipe, which involves 35 passes, but it seems overkill.

Unlike conventional HDD, one pass is more than enough.* The real problem comes from the damaged block partition which you can't destroy so easily.

Most SSD vendors offer utilities which do a nuke n destroy for their brand. Some motherboards offer it too.

*To be honest: Forensic data recovery was based on that fact there was subtle head movements while the HDD was recording. So there's a clean data area in the middle where the data is confirmed to be overwritten then there's a fuzzy outer track area where the data may or may not be overwritten. So data recovery experts would micro tune the head to adjust it's track position to find exactly where the old data was written. But today's drives are so tightly packed track wise that a single random data wipe will destroy the vast majority of all data unless that old data was on a marked damaged block.
 
Unlike conventional HDD, one pass is more than enough.* The real problem comes from the damaged block partition which you can't destroy so easily.

Most SSD vendors offer utilities which do a nuke n destroy for their brand. Some motherboards offer it too.

*To be honest: Forensic data recovery was based on that fact there was subtle head movements while the HDD was recording. So there's a clean data area in the middle where the data is confirmed to be overwritten then there's a fuzzy outer track area where the data may or may not be overwritten. So data recovery experts would micro tune the head to adjust it's track position to find exactly where the old data was written. But today's drives are so tightly packed track wise that a single random data wipe will destroy the vast majority of all data unless that old data was on a marked damaged block.

By conventional, you mean old, right?
 
Oh, I see. Well, in this case, I asked the original thread question based on how many times you needed to wipe a mechanical hard drive because that's what I'm wiping, not an SSD.

If it's a mechanical, 3 passes should do it for most drives 1tb and above. That will stop 99.99% of conventional recovery efforts.

If its really sensitive data and somebody wants it bad enough, a couple drill bits through the platters and controller after a wipe. (Seriously). Hammers work nicely too.