tag:blogger.com,1999:blog-2807403883562053852.post1362748063950634500..comments2024-03-27T08:40:31.785-06:00Comments on Clayton Cramer.: Wiping Free Space UtilitiesClayton Cramerhttp://www.blogger.com/profile/03258083387204776812noreply@blogger.comBlogger10125tag:blogger.com,1999:blog-2807403883562053852.post-2130814384791939942012-01-17T06:46:06.730-07:002012-01-17T06:46:06.730-07:00We use Darik's Boot and Nuke. Open source. Sin...We use Darik's Boot and Nuke. Open source. Single or multiple passes. If you want 100% assurance, use the old HDD as a rifle/pistol target.Marc C.https://www.blogger.com/profile/05593002055776765614noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-59282515060253365892012-01-12T08:23:33.782-07:002012-01-12T08:23:33.782-07:00I regularly use Nathon's method to reduce the ...I regularly use Nathon's method to reduce the compressed size of image backups, although I set the block size of both to 1M or 4M(egabytes) so that trips to and from the kernel have no chance of being the rate limiting step.<br /><br />I.e.:<br /><br />dd if=/dev/zero of=whatever bs=4M<br /><br />And dd is so basic you can be sure it's not been gimmicked.<br /><br />(If you want to get really good at inexpensive backups, get W. Curtis Preston's fantastic <a href="http://www.amazon.com/Backup-Recovery-Inexpensive-Solutions-Systems/dp/0596102461/" rel="nofollow">Backup & Recovery</a>, which despite the subtitle tells you when you should consider commercial solutions.<br /><br />But if you know UNIX(TM)/Linux, you can setup a good Windows backup system that will save your bacon when something <a href="http://www.ancell-ent.com/1715_Rex_Ave_127B_Joplin/images/" rel="nofollow">like this</a> happens, as long as you include using some form of rsync to a offsite repository like rsync.net. My Windows system was right next to my balcony door and I would have e.g. lost a lot of my email if not for taking such steps (of course, it wasn't accidental my backup system was designed to handle a tornado given where I live).)<br /><br />BTW, my favorite live cd for this sort of thing is <a href="http://en.wikipedia.org/wiki/SystemRescueCD" rel="nofollow">SystemRescueCD</a> because I've reluctantly abandoned BSD, which I started using in 1981 (sic; bare-metaled a PDP-11/44 to BSD 2.x then)).ThatWouldBeTellinghttps://www.blogger.com/profile/16910231314995266781noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-9464527879270620512012-01-12T04:33:04.098-07:002012-01-12T04:33:04.098-07:00Personally, I'm looking for a good Defrag. No...Personally, I'm looking for a good Defrag. Not like what the Windows Defrage or Defraggler do. Well, on the Mac that was called Defragging, I've since learned on the PC it's called "Optimizing" where files are not only made contiguous, but the free space as well.Mauserhttps://www.blogger.com/profile/11732614352398473302noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-22848548183918273462012-01-11T16:43:10.329-07:002012-01-11T16:43:10.329-07:00Nathan's method should work, though you might ...Nathan's method should work, though you might get better results using if=/dev/random and running it twice. Check to see if the drive is sellable for enough to make it worth not using for target practice.Anthonyhttps://www.blogger.com/profile/12389602137217799305noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-266109937886714202012-01-11T16:42:44.300-07:002012-01-11T16:42:44.300-07:00Nathan's method should work, though you might ...Nathan's method should work, though you might get better results using if=/dev/random and running it twice. Check to see if the drive is sellable for enough to make it worth not using for target practice.Anthonyhttps://www.blogger.com/profile/12389602137217799305noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-37590951410057046732012-01-11T15:02:18.303-07:002012-01-11T15:02:18.303-07:00What's the manufacturer of the HD? If you poke...What's the manufacturer of the HD? If you poke around the manufacturer's website, some of them hand out a bootable .iso you can burn to CD. Then boot that, and it has an option to write zeroes to the entire HD. I've used Western Digital's utilities to do just that.<br /><br />If you're on the cheap, boot a *nix boot/install .iso. (I generally use FreeBSD 8.1's liveFS disc) Fire up a command prompt, and do<br /><br />dd if=/dev/zero of=/dev/hda obs=4096<br /><br />That reads from /dev/zero -- which is as it sounds -- and writes it to /dev/hda , which is the first drive on Linux. It's /dev/ad1 on FreeBSD here. Do some ls'ing in /dev to determine the correct path. The obs=4096 means it writes 4K at a time. May take overnight to write out zeroes over the entire HD.Nathan Mateshttps://www.blogger.com/profile/08470811704428376199noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-77253857849231007472012-01-11T11:59:33.446-07:002012-01-11T11:59:33.446-07:00Sigivald: Thanks for the additional information. ...Sigivald: Thanks for the additional information. I was not particularly worried about the FBI or NSA recovering my data.Clayton Cramerhttps://www.blogger.com/profile/03258083387204776812noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-24358688996736291112012-01-11T11:37:40.736-07:002012-01-11T11:37:40.736-07:00One pass will work fine; the idea that multiples a...One pass will work fine; the idea that multiples are needed is very-widespread urban legend (with some minor historical basis in fact).<br /><br />The old <a href="http://www.cs.auckland.ac.nz/~pgut001/pubs/secure_del.html" rel="nofollow">Gutmann</a> paper detailed 35 various pass patterns for erasing drives, <i>based on the specific coding used</i> - no drive needed all of them, even then; modern drives, however, are easily erased with a single pass of random data (per Gutmann himself in the appendix).<br /><br />(And <a href="http://www.nber.org/sys-admin/overwritten-data-gutmann.html" rel="nofollow">contra</a> his hypothesis of using a magnetic field microscope to "read" the data previously held, it's not remotely sure that anyone can do it even in theory, and in any case it's irrelevant to your needs.<br /><br />Me, I never even bother trying to sell old drives; the transaction cost very nearly exceeds the value of them, and they're more useful in a case a portable drive anyway...)Sigivaldhttps://www.blogger.com/profile/16152366541957466049noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-61514152774402919572012-01-11T10:18:08.998-07:002012-01-11T10:18:08.998-07:00I have used Eraser for a long time now. It is qui...I have used Eraser for a long time now. It is quite versatile as to the level of security and will overwrite free disk space and swap files nicely.Dave in St. Louishttps://www.blogger.com/profile/13740394116408232360noreply@blogger.comtag:blogger.com,1999:blog-2807403883562053852.post-72347131788125781262012-01-11T10:13:53.423-07:002012-01-11T10:13:53.423-07:00I found Eraser - http://sourceforge.net/projects/e...I found Eraser - http://sourceforge.net/projects/eraser/ to be very good. <br /><br /> It will overwrite the entire hard drive. If you set it for 7 passes, expect it to take all night plus some for it to write-over your hard drive multiple times.<br /><br />Between using it to wipe the drive with the maximum number of passes and and then doing a complete reformat and reinstall of Windows Vista I was not very concerned when I returned the computer to HP after they were unable to fix a recurring problem with it during the warranty period.Aaronhttps://www.blogger.com/profile/08146728790019377401noreply@blogger.com