Overwrite existing partition with zeros without hurting partition table? (Debian Lenny)
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From: Ron Johnson on 6 Mar 2010 22:20 On 2010-03-06 20:52, Mark wrote: > Bringing this thread to a close as I'm the OP: > > 1) Thanks to the people who actually provided help. > > 2) To the others, isn't one of the purposes of Linux to allow us to do > what we want, how we want, when we want? I have a preference to blank > hdd sectors with zeros before doing a new OS installation; I've done it > for years with DBAN, etc., on various operating systems. If you think > it's pointless, senseless or whatever else, fine, but FWIW, on the 20 GB > partition, it took all of 5 minutes using the dd command from an Ubuntu > Live CD. FIVE MINUTES. And I know the hdd is good as new and ready to > accept fresh data. > > 3) For anyone else who wants to do it, I wound up doing two things: > blanking the MBR with "dd if=/dev/zero of=/dev/sda bs=446 count=1" and > the hdd partition with "dd if=/dev/zero of=/dev/sda2 bs=1M". > > Now, go ahead and judge me for blanking the MBR even though the > installation went perfectly and the MBR blank took less than 1 second. :) > We're allowed to question *spurious* justifications. If you'd have said "for privacy concerns" instead of fear of "ghost/residual files", the response would have been markedly different. Maybe you really meant "privacy" when you wrote "ghost files", but we, or -- more specifically, I -- can not know your inner thoughts. -- Ron Johnson, Jr. Jefferson LA USA "If God had wanted man to play soccer, he wouldn't have given us arms." Mike Ditka -- To UNSUBSCRIBE, email to debian-user-REQUEST(a)lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster(a)lists.debian.org Archive: http://lists.debian.org/4B931968.4030900(a)cox.net
From: Mark on 6 Mar 2010 23:20 >On Sat, Mar 6, 2010 at 7:11 PM, Ron Johnson <ron.l.johnson(a)cox.net> wrote: [snip] > >We're allowed to question *spurious* justifications. If you'd have said > "for privacy concerns" instead of fear of "ghost/residual files", the > response would have been markedly different. > > > Interesting, so what is the difference in terms? Wouldn't the privacy concerns be from residual files? Mark
From: Ron Johnson on 7 Mar 2010 02:30 On 2010-03-06 22:10, Mark wrote: > >On Sat, Mar 6, 2010 at 7:11 PM, Ron Johnson <ron.l.johnson(a)cox.net > <mailto:ron.l.johnson(a)cox.net>> wrote: > [snip] > > >We're allowed to question *spurious* justifications. If you'd > have said "for privacy concerns" instead of fear of "ghost/residual > files", the response would have been markedly different. > > > > > Interesting, so what is the difference in terms? Wouldn't the privacy > concerns be from residual files? > Yes, but... residual *files* just DO NOT EXIST ANYMORE after a mkfs. What *can* exist, maybe, are residual *fragments* (blocks or sectors, since the original inodes and index structures were wiped away by the mkfs) which a clever forensic technician could maybe piece back together, So, zeroing out the partition is a reasonable operation for a /home or /data partition (where you'd keep sensitive data), but not for something as mundane as an OS-only / partition. BTW, I like having a separate /data (or whatever you all it) partition, and recommend that you also having a separate /home. -- Ron Johnson, Jr. Jefferson LA USA "If God had wanted man to play soccer, he wouldn't have given us arms." Mike Ditka -- To UNSUBSCRIBE, email to debian-user-REQUEST(a)lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster(a)lists.debian.org Archive: http://lists.debian.org/4B935482.80402(a)cox.net
From: Eduardo M KALINOWSKI on 7 Mar 2010 06:50 On 03/07/2010 04:23 AM, Ron Johnson wrote: > What *can* exist, maybe, are residual *fragments* (blocks or > sectors, since the original inodes and index structures were wiped > away by the mkfs) which a clever forensic technician could maybe > piece back together, > > So, zeroing out the partition is a reasonable operation for a /home > or /data partition (where you'd keep sensitive data), but not for > something as mundane as an OS-only / partition. > However, I was under the impression that the OP wanted to zero a disk he already owns and intend to continue owning. I'd definitely zero (or write random bytes) a disk that I'd give or sell, but if I wanted just to clear the disk for my own use, I don't think I need to protect my confidential stuff from myself. -- /* now make a new head in the exact same spot */ -- Larry Wall in cons.c from the perl source code Eduardo M KALINOWSKI eduardo(a)kalinowski.com.br -- To UNSUBSCRIBE, email to debian-user-REQUEST(a)lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster(a)lists.debian.org Archive: http://lists.debian.org/4B9392AB.1070201(a)kalinowski.com.br
From: thib on 7 Mar 2010 12:30
Just to drop my two cents, since no one did before: Merely zeroing is not enough [1]. [1] http://en.wikipedia.org/wiki/Data_remanence -- To UNSUBSCRIBE, email to debian-user-REQUEST(a)lists.debian.org with a subject of "unsubscribe". Trouble? Contact listmaster(a)lists.debian.org Archive: http://lists.debian.org/4B93E204.9080505(a)stammed.net |