From warmfuzzy@700:100/0 to All on Mon Jul 2 20:50:08 2018
You might have heard about "secure deletion" of hard drives before they are repurposed in giving them to charities or sold for a bit of cash. One of the most used "algorithms" is a simple "zeroing" of a disk where all the same "character" is used to fill the whole drive. The problem with this is its
not random, but rather a universal wipe of the whole drive with a single element. Because of this the information is still there on the drive, its
just offset a bit, so to recover the stuff on the disk you would just need to remove the "shift" of characters and the original content reappears. You see using a single character to wipe a drive with means that it offsets the data
by a "known" element, and simply correcting for that character reveals what
was previously on that hard drive. I suggest using eight passes of a pseudo-random number generator (PRNG).
From danly@700:100/3 to warmfuzzy on Tue Sep 11 01:09:15 2018
GNU Shred's default settings are generally Good Enough for _older_ disks, however... SSDs and platter drives with non-volatile caching can thwart even the best efforts to wipe them, as they'll aggressively avoid read/write wear
in a manner that makes it so that the predictability of where writes occur is no longer reliable. The only good way to dispose of modern discs is by
melting them down.