How can I securely format a solid-state drive?

Question

When selling / throwing away / giving away HDDs I always use DBAN to do a DoD wipe first.

Is this still a valid thing to do on an SSD?

Will it have an adverse effect on the SSD's lifespan?

Solution 1

After the fact, but things have changed a lot in the last 10 months or so - a lot of SSD manufacturers are including (or will be soon) a secure erase function in their optional software utilities that will do the single wipe pass for you properly from a controller level. (I know Intel already has this and it works great.)

Solution 2

I agree with Molly minus the encryption. Encryption is a good way to protect data, but it doesn't erase it.

If you want to erase the whole SSD, DBAN on a single pass would work. I would set it to pseudorandom so if anyone looked it would look like it could be encrypted.

If you want to only wipe a file, using a conventional wipe program (one for a hard drive) would only make it save from undelete tools. I don't know of any data carving tools that are SSD/flash wear leveling aware, but I'm sure if they aren't out there, they will be. The most effective way to wipe a file from a SSD/flash is to fill all the free space.

All that said, I don't know if all the spare cells in the flash would be overwritten. (Most flash have spare cell just like hard drive have spare sectors.)

Also, strictly speaking, overwriting (no matter the passes done) is no longer authorized by the DoD to sanitization hard drives. Also, many software say DoD wipe but do the 3-pass and not the 7-pass. In addition, I hear from many people talking about hard drive magnetics and the best wipe is a multipass random pattern. They say having a known pattern would make reconstruction easier.

Comments

[Admin]

Also see Reliably Erasing Data From Flash-Based Solid State Drives by Wei, Grupp, Spada, and Swanson.

[Ravindra Bawane]

This. Most SSD utilities now include this function built in. It is a standard built into the ATA specification called ATA Secure Erase, and the drive utilities trigger this process on the drive.