-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On Sat, Nov 12, 2016 at 01:25:50PM -0600, Richard Owlett wrote: > On 11/12/2016 12:26 PM, Pascal Hambourg wrote: > >Le 12/11/2016 à 18:22, Richard Owlett a écrit : > >> > >>>>ddrescue /dev/sda /mnt/defective_drive.img > >>>>/mnt/defective_drive.log > >(...) > >>Can this be run as a user, or are root permissions required. > > > >Unless the user has read permission on the raw device, it must be > >run as root. > > I have a STRONG suspicion that by "raw device" you refer to the > defective device which is enumerated as /dev/sdc . *ALL* > documentation and tutorials I found make a *MAJOR POINT* of *NOT* > mounting the defective device. "Permissions" therefor are a murky > issue.
In this case, the permissions on /dev/sdc were meant (as opposed to the permissions on the files whithin the file system in /dev/sdc, which don't count in this case) > Point of fact, the specific physical defective object > predates me having more than casual interest in *nix. Yes: I remember there's a DOS file system in the disk in question, so no permissions in there anyway. But as stated above, this doesn't matter, because you're looking at the container: access to that is ruled by the permissions on the device file, i.e. /dev/sdc. > There's a reason I asked for "hand holding" and specifically asked > for tolerance. > In a "user to user" support enviroment ther is an expectation of > querent doing his due diligence. I tried. I failed. M'aidez s'il > vous plait. In a nutshell: you mount your *new* disk to a directory of your choice (let's say /mnt). Possibly your OS is set up to do that for you: it'll typically end then somewhere in /media/blah (for some suitable value of "blah"). Let's use /mnt as a placeholder. Then you insert you defective disk, which (let's say) appears as /dev/sdc. Make sure the OS doesn't mount it automatically, otherwise unmount yourself. Then you do dd if=/dev/sdc of=/mnt/my-disk-backup bs=4096 count=1000000 (this is over-simplified: you'll probably use ddrescue instead of dd, or at least use the option 'noerror'). An image of your disk will hopefully appear on 'my-disk-backup'. You need read access to /dev/sdc and write access to the directory /mnt (either by doing sudo, I'd do that or by other means). Those steps are a rough sketch. Many details already flew back and forth in this thread, so I didn't want to bloat the thing too much. Feel free to ask where things are unclear. Regards - -- tomás -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.12 (GNU/Linux) iEYEARECAAYFAlgngikACgkQBcgs9XrR2kYjmACeJyeAvYCCrcfx2UuSglH7Dnvb eg0An14EEu9c0jwQTcjF5/4bNCm9qHTV =c2+e -----END PGP SIGNATURE-----
