On Tue, 2015-08-18 at 21:10 +1200, Volker Kuhlmann wrote: > On Tue 18 Aug 2015 14:21:04 NZST +1200, Adrian Mageanu wrote: > > > I can't remember where I read but there are ways to retrieve data after > > a dd fill with zeroes or something else by using photorec and some > > hardware forensic techniques. > > Really? I doubt that. What kind of "hardware forensic techniques"? > Dismantling the drive and using equipment worth 6 digits or more is a > fairly good protection for Joe Bloggs. > > I still don't see how you can practically improve on dd'ing zeros. To be > better than that you'd need to destroy the platter. Unless the drive > firmware implements erased-data recovery functions. Does it? Hard drives > are a highly competitive commodity, do you think manufactures spend any > time developing features that Joe Henry never knows about and which never > get mentioned in any specs? > > If I'm wrong I'd like to hear. Please note the "Gutmann method" of the > 1990s is only applicable to drives last manufactured in the 1990s. > > Volker >
I'm ready to stand corrected here, I'm not a specialist in this field. It was some 3 or 4 years ago when I did this and at the time, when searching for a solution to securely wipe the disks, I found about dban and nwipe. I already knew about the dd method. I remember that back then I did a search for dd vs dban and in one of the pages I read that it is possible to recover data from a disk wiped with dd. In the same search I found nothing regarding recovering data from disks wiped with dban. I didn't bookmarked that page and I tried to find it know, but no luck, sorry. >From memory, the method described was a combination of utilities of which I can only remember photorec, and one of the forensic techniques described (among others) was a way to read the disk by offsetting the head left and right by only tiny amounts for each pass. I don't remember reading about a success rate and I wasn't interested in the process itself, just if a recovery was possible and what method of wiping a disk - dd or dban - was more secure. One thing is sure, if there will be a next time when I'll need to decommission a hard-disk, I'll follow this list's wisdom and use either dd or a hammer + magnets. Or both. dban is taking way too long. Adrian _______________________________________________ Linux-users mailing list Linux-users@lists.canterbury.ac.nz http://lists.canterbury.ac.nz/mailman/listinfo/linux-users
