Re: Help with ddrescue
On Fri, 08 May 2015 19:52:04 -0400
The Wanderer <email@example.com> wrote:
> On 05/08/2015 at 07:33 PM, German wrote:
> > On Fri, 08 May 2015 19:20:37 -0400
> > The Wanderer <firstname.lastname@example.org> wrote:
> >> On 05/08/2015 at 07:08 PM, German wrote:
> >>> That's what I got:
> >>> spore@asterius:~$ lsblk
> >>> NAME MAJ:MIN RM SIZE RO TYPE MOUNTPOINT
> >>> sda 8:0 0 119.2G 0 disk
> >>> ├─sda1 8:1 0 512M 0 part /boot/efi
> >>> ├─sda2 8:2 0 111.3G 0 part /
> >>> └─sda3 8:3 0 7.4G 0 part [SWAP]
> >>> sdb 8:16 0 465.8G 0 disk
> >>> sdc 8:32 0 1.8T 0 disk /media/spore/9F86-0131
> >>> sdd 8:48 0 1.8T 0 disk
> >>> └─sdd1 8:49 0 1.8T 0 part
> >>> Where sdd is my failed drive. sdc is my spare drive. The correct
> >>> procedure will be ddrescue if=/dev/sdd1 of=/dev/sdc ?
> >> No. That might potentially work (except that, if I'm reading the
> >> ddrescue man page correctly, the syntax is wrong), but it wouldn't
> >> be correct.
> >> First, unmount /dev/sdc.
> Note for the record: The other steps will erase any data which is
> presently on /dev/sdc. I figure you probably already know that, but I
> just want to be explicit about it.
> >> Then do one of two things:
> >> 1) Create /dev/sdc1 (as an unformatted partition, using fdisk or
> >> parted or whatever partitioning tool you choose), and then run
> >> ddrescue /dev/sdd1 /dev/sdc1 /any/path/you/want/ddrescue.log
> >> 2) run
> >> ddrescue /dev/sdd /dev/sdc /any/path/you/want/ddrescue.log
> > Ok, I think I am getting closer. How big is a log file?
> The size of the log file depends on two things: the size of the data
> source which is being copied/rescued, and the number of errors which
> occur while attempting to read that data source.
> It can be very small, or it can be moderately large. Even in a
> ridiculous case, however, I wouldn't expect it to be more than a few
> hundred megs - unless the source drive is so bad that you're not going
> to be getting any data back off of it anyway.
> > Can it be anywhere on all drives that have enough space? For
> > instance:
> > ddrescue /dev/sdd /dev/sdc /dev/sda2/ddrescue.log will work?
> Not quite. /dev/sda2/ is not a directory; it's a device node.
> Since /dev/sda2 is mounted to / (the root filesystem), the correct
> equivalent to this command would be:
> ddrescue /dev/sdd /dev/sdc /ddrescue.log
> and although I wouldn't advise storing a log file in the root
> directory, the command should work.
> The log file itself can be placed in any writable location which has
> enough space.
Thank you I started ddrescue and it is going somewhere. Probably will
take 10 hours or more to complete. I'll let you know how it's all went.
Thank you once more. It refused to work as we wanted and asked for
--force option ( -f)