>but it's probably not enough to persuade other people that it's gone.
I believe there is a long standing bounty for anyone who can retrieve useful data from a drive that had been zero'd once. No one has been able to thus far.
A lot of the disk wiping "culture" stems from a much earlier time when disk technology was less reliable, especially in regards to writes. Dan Gutmann himself says that the Gutmann method is long antiquated and only worked with MFM/RLL encoded disks from the 80s and early 90s.
Perhaps instead of humoring these people, we should be educating them. A zero'd out disk is a wiped disk until someone proves otherwise.
This reminds me of assertions we used to take for granted about DRAM. We used to assume that the contents are lost when you cut the power, but then someone turned a can of cold air on a DIMM. We usually assume that bits are completely independent of each other, but then someone discovered the row hammer. The latter is especially interesting because it only works on newer DIMM technology. Technology details change, and it's hard to predict what the ramifications will be. A little extra caution isn't necessarily a bad thing.
I agree but redoing a wipe isn't extra caution, its just literally repeating the same thing. If that thing is wrong, you're not helping the situation, just wasting time/resources.
Extra caution would be shredding the drive or some other non-wipe method. At work for example, we zero out drives and then those drives get physically destroyed by a vendor.
Gutmann's paper talks about a time when you didn't know what drive controller was used, and so he created a set of patterns to be used for each pattern. That comes to (about) 35 different patterns.
This gets misunderstood as "you need to do 35 passes of these patterns". You don't, Gutmann recommends a couple of overwrites of random data, and a single overwrite of zeros is probably enough.
I believe there is a long standing bounty for anyone who can retrieve useful data from a drive that had been zero'd once. No one has been able to thus far.
A lot of the disk wiping "culture" stems from a much earlier time when disk technology was less reliable, especially in regards to writes. Dan Gutmann himself says that the Gutmann method is long antiquated and only worked with MFM/RLL encoded disks from the 80s and early 90s.
Perhaps instead of humoring these people, we should be educating them. A zero'd out disk is a wiped disk until someone proves otherwise.