I ran across this Hacker News discussion about ShredOS, which is a utility designed to securely erase data from a hard drive.
This is one of a number of available tools that attempt to render data unrecoverable by overwriting the hard drive with other data. ShredOS has an impressive number of options, from a basic “fill the device with 0s” to DoD 5220.22M compliant wiping, which requires overwriting the data 7 times.
The Hacker News discussion notes that this doesn’t really work for SSDs, and there is some discussion about alternative methods for those.
I used to use tools like this when disposing of hard drives, but instead, opt for this process now:
- All the drives I use are encrypted with a long, unique passphrase key.
- When I’m ready to dispose of a drive, I change the encryption key to a random string that I do not record anywhere.
- Have the drive physically destroyed.
A bit paranoid? Absolutely, but a small price to pay to never worry about that drive again.