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10.4: Recover a dead hard drive using GNU ddrescue UNIX
Tiger only hintI had a problem with my disks (an original Maxtor from a dual G5). It had three HFS Plus journaled partitions. Suddenly, the system would not boot. When looking at the disk with Apple's Disk Utility, the disk is visible, the name of the volume is not displayed (/dev/disk0s5 was displyed instead), and the volume would not mount. Using Apple's Disk Utility repair function failed to fix the drive.

I tried using DiskWarrior, but it was really slow -- the message was saying something like "speed inhibted by disk malfunction." It was so slow, I was not sure if it had crashed, or if it would take weeks to get through. So I decided to look what other tools were available, I looked on macosxhints, and found this article about using dd to make a block copy of a volume (e.g. /dev/disk0s5). Then, looking aroung on the net, I found a Linux tool called GNU ddrescue made by Antonio Diaz Diaz (not to be confused with dd_rescue written by Kurt Garloff, which was mentionned in one of the comments of the original article).

I tried to compile ddrescue on Panther and it did not work. I then tried to compile it on Tiger, and it worked the first time (great to see Linux tools compiling on OS X without causing a headache). To compile, open the Terminal and cd to the ddrescue directory, and then run the following commands:
$ ./configure
$ make
Then you can run ddrescue (once compiled, it would probably also run on 10.3).

The syntax for ddrescue is quite simple and here are the steps I followed:

Copy the content of the volume into an image file:
sudo ./ddrescue -v /dev/disk0s5 MyVolImage.dmg MyVolRescue.log
The were errors reported during the copy of few blocks. ddrescue retried several times until I considered that there was no hope to recover these dead blocks (initially there were read errors on about 3000 blocks, and at the end, it turned out that 900 blocks had died). The computer really slows down (everything freezes) during that kind of operation.

I was monitoring the action by looking at the log ddrescue produces, and using this command:
$ sudo fs_usage | grep ddrescue
A cool feature of ddrescue is that you can stop and resume its activity. It will use the log file to pick up where it stoped last. Then I tried to mount the image file, but it did not work. I don't know why not; maybe because it was an HFS Plus journaled partition.

So I got a new disk (to be sure there were not bad blocks and to keep the original disk intact, just in case) and created a partition with pdisk of the exact same size (number of blocks) of the original partition (and the image file, remember a block is usually 512 bytes). Then I used ddrescue to copy the image file back onto the new partition:
$ sudo ./ddrescue -v MyVolImage.dmg /dev/disk1s3 MyVolRestore.log
I was then able to run DiskWarrior to repair the remaining problems (faster this time because there were no bad blocks) on that new partition. After that, I was able mount the volume and get my most important files back.
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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: lewsmind on Jul 28, '05 10:38:29AM

That is a pretty impressive solution. Nice job. I'll have to file this away, just in case.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: trollll on Jul 28, '05 03:24:17PM

okay, need to try this...

stupid maxtor drive (replacement for the other one that died) lost a partition with some very important files almost two years ago. haven't touched it since then other than to give another rescue method a shot.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: khedron on Jul 28, '05 03:39:01PM

The amount of time diskwarrior takes can definitely vary widely: although it often takes only a few seconds to run, I've heard of it taking as long as three days on a damaged hard drive... and successfully restoring a system that had been unable to start up before.

On the other hand, I once tried to run it on a damaged hard drive, and after about a day, it finally finished, and when it tried to overwrite the old directory data with the rebuilt data, gave me a message saying that there was a write error, and diskwarrior had just unintentionally destroyed ALL directory data, and that while some files were accessible at that moment, the next time I restarted everything would be gone. Oops.

At this point, I ran a Norton program... Norton Volume Recover, I think it's called. It can rebuild the directory from scratch by scanning the entire hard drive for bits of files. I wasn't expecting it to help at all, as I haven't been impressed with Norton recently, but it miraculously managed to restore virtually every file on the hard drive, succeeding where every other program I tried had failed. (I had not been running Filesaver, or whatever it's called, which collects data to aid Volume Recover in case of an emergency.)

So that's a tool that's now a permanent part of my collection.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: mathias01 on Jul 29, '05 11:34:41AM

DiskWarrior has an often overlooked preview option. If you have rebuilt a drive you suspect of having problems, click on the "Preview" button in the lower left hand corner, and DiskWarrior will mount a read-only version of the drive. This drive shows up to other disk utilities as a real drive, and I've had very good luck imaging from this preview drive using utilities like carbon copy cloner. I do agree that it is rather impolite of DiskWarrior to dump the rebuilt directory with no warning if it encounters a problem during the replacement.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: johnsawyercjs on Sep 06, '05 07:49:27PM

The publisher of Diskwarrior, Alsoft, claims that Diskwarrior's directory replacement process won't wipe the old directory until it's successfully written the replacement directory (unless there isn't enough free space for the replacement directory, in which case Diskwarrior will write over the old directory, which can be unsafe if there's a power outage, a crash, etc.), but sometimes, especially on drives that have bad blocks, this guarantee doesn't hold up. Whenever you see Diskwarrior report "Speed inhibited by disk malfunction", it means the drive has bad blocks, and you shouldn't let Diskwarrior try to replace the directory--as mathias01 says, use Diskwarrior's Preview option to Finder-mount the results of Diskwarrior's scan, and copy your files from that preview volume to a backup drive.

The commercial utility "Data Rescue", from ProSoft, will do essentially what Bruno's hint describes, with a convenient GUI--it will scan the whole hard drive for files, and if it encounters a bad block, it will spend a reasonable amount of time retrying to read the block, and eventually will give up and go on with the rest of the drive. It doesn't spend too much time trying to read a bad block, but if the drive has a lot of bad blocks, it can still take many hours or even a full day (or longer). If the command line utils described in this hint let you change the amount of time spent retrying bad blocks, that would sometimes be very useful, since usually a bad block can't be read no matter how many times the utility tries, but as Bruno describes in his hint, sometimes letting the util keep trying is a good thing, since his drive had around 3000 problematic blocks, but only 900 had completely died--the utility may have been able to get data from some of the problematic blocks because it kept trying to read them.

The feature of ddrescue that lets you stop its scan, and resume it later using the log file it generates, sounds pretty handy--I don't think Data Rescue has that feature, and I know Diskwarrior doesn't.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: mproud on Jul 28, '05 04:59:31PM
Isn't the standard procedure

make install


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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: vykor on Jul 28, '05 06:37:52PM

Make install would just put a copy of the binary in /usr/local/bin (if you didn't configure it with some other prefix). You could do that, or you could just run it out of the build directory if you don't want to install the binary into the official binary directory, for whatever reason. This particular piece of software ought to work either way.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: DuallyG5 on Sep 05, '05 10:24:28AM

I can't seem to get it compiled
./configure says

prefix = /usr/local
datadir = $(prefix)/share
infodir = $(datadir)/info
mandir = $(datadir)/man
OK. Now you can run make.

so now what ? any ideas ???

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: derrickbass on Jul 29, '05 03:52:16AM

I'm a little confused by exactly why the disk image is being used. If you already have a blank disk you are going to use for a rescue volume, you can just use ddrescue straight onto that disk and then use Disk Warrior to fix any damage.

I should also point out that if you don't have a rescue volume, you can use Disk Warrior (or pretty much any other disk repair program) to repair an image directly. If the image won't mount, go to the the command line and type
hdiutil attach -nomount image.dmg
Then launch DiskWarrior. If the disk image is not too badly damaged it should see it and be able to repair it.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: Gregory on Aug 10, '05 11:41:28AM

my situation: one firewire disk enclosure, two drives.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: jklos on Jul 31, '05 03:06:24PM

That's cool that it works, but although nitpicky, this isn't a "Linux" tool. Linux is a kernel. Most of the rest of what people call Linux (ie, the rest of the OS besides the kernel) is GNU. This tool is GNU. Linux has nothing to do with it.

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recover more blocks using 'raw' devices
Authored by: krishna on Jan 08, '06 10:45:07PM

I just finished recovering (under a linux box I set up to be dedicated for the recovery operation) a fat32 partition that was giving me errors on what appeared to be multiple blocks. Then I followed 'info ddrescue' 's information on setting up a raw device and retrying the recovery, it came down to a single 512-byte sector (!) that was bad and producing multiple block errors.

So if I can find which file that block belongs to, I have my whole partition back. While ddrescue's not a linux-specific tool, that valuable 'raw' information in the documentation is definitely linux-specific; so I wouldn't say I wouldn't say ddrescue has *nothing* to do with Linux, since it definitely seems to be the chosen platform for testing. Of course, information on raw devices under macosx would be awesome to have.

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recover more blocks using 'raw' devices
Authored by: Detrius on Jun 30, '10 10:03:48AM

On OS X, raw disks are:


Block devices are:


If you use rdisk, ddrescue will pull the data MUCH more quickly--of course, depending on the state of the drive.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: Applesmurf on Jul 11, '06 04:31:56AM

Install Xcode tools from the Tiger cd or the developer tools. You need a compiler to do this and gcc is installed with Xcode.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: bcreane on Oct 07, '06 08:48:25PM
Once you create a copy of your drive using ddrescue, you can use testdisk and/or photorec to search the disk for recoverable files. Check out: for more info.

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***Beware deletion of data***
Authored by: TC!! on Nov 02, '06 03:18:41PM

Hopefully this is just something I did wrong, but I ended up wiping another hard drive on my machine.

I had one disk fail on and old headless B&W g3, it contains 2 disks, 20GB which has the system on it and an 80GB drive for data which died. Diskwarrior qwouldn't even see the volum and in disk utility it was shown as disk1s10.

I attached a firewrie drive with one empty 80GB partition and used ssh to remotely log into the machine. I had already copied ddrescue into my home folder on the drive. So I tried this command first:
sudo ./ddrescue -v /dev/disk1s10 /Volumes/Video/Biggy.dmg Biggy.dmg

Video is the name of the empty firewire disk and Biggy was the hard disk which failed. After running that it seemed to start and then paused. It then quit with an error message telling me it couldn't write the log file. A quick ls showed me the directory I was in was empty. I tried to access the drive remotely and could see directories disapearing as I moved around folders. In the end I was left with just the system files.

I tried again, this time saving the log file onto the firweire disk. It seemed to go a little further and then I lost alll contact with the machine, it had crashed completely. This may have been due to the missing files or the system files where deleted as well.

Im not going to be able to check until I can get a monitor to boot the machine adn try using disk warrior to repair the system disk. I'll try a recover tool to get the files I've lost off the system disk. I think I'll have to do that first and then reinstall the system.

If anyone can see what I did wrong then please let me know, if not then please beware this application in case it caused the deletion. I think I'll completely give up on two drives in a rev 1 B7W G3.

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To mount or not to mount?
Authored by: Andrman on Feb 18, '07 08:27:26PM

I am currently running ddrescue on my PowerBook's former internal drive per this hint. It's finally gotten to the error-ridden area and I'm looking forward to seeing what I can recover.

Reading the INFO that came with ddrescue, I found this:

"IMPORTANT! Never try to rescue a r/w mounted partition. The resulting copy may be useless."

My old drive is connected through a USB-ATA adapter and is mounted on the desktop. Should I have not mounted it? I did not see this specified anywhere in the hint or comments - I hope I haven't wated my time (and the integrity my drive has left).

I manually stopped the process when it was about 80% through and tried to mount and got a "not recognized" error. I'm not sure if this was because the image was incomplete or because I didn't do it right.

If so - what is a good way to connect the drive to the computer without mounting it? Command-line or UI instructions would be fine... I'm not very experienced in any of these UNIX practices.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: paulhagstrom on Jul 21, '07 03:09:56PM
Just wanted to add a note here: This also works well with floppies. I finally decided to image all of my floppies and then throw the floppies away, given that most of the media is over a decade old. It went pretty well using Disk Utility's disk image creation, but where a disk had a bad sector on it, DU refused to do anything with it. This ddrescue program did a nice job of preparing me to use DiskWarrior to repair. I still have only DiskWarrior 3.03, on a PPC machine, and there are some issues with the preview mode, but I've found that if Classic is running, DW seems to work. Who knows why, maybe it's just superstition, but I don't think it is entirely. Anyway, I did the following, in the terminal:
  • Insert the disk
  • df
  • Locate the floppy drive, say /dev/disk6
  • If the floppy mounted, unmount it by:
    diskutil unmount disk6
  • Run ddrescue:
    ddrescue -v /dev/disk6 ddr_sda159.dmg sda159.log
  • Eject the disk:
    diskutil eject disk6
Then, mount the resulting image (ddr_sda159.dmg in this example, double-clicking on it will do the trick), switch over to DiskWarrior, rebuild, preview. Switch over to Disk Utility, select the rebuilt volume (with the DW icon), convert the image. Back to DiskWarrior to cancel, and then finally unmount the original image. It worked quite nicely for those disks that had only a tiny amount of damage. I haven't had any that actually didn't mount at all, so parts of this procedure may need to be tweaked for that scenario. Specifically, the part where I mounted the disk image that ddrescue produced might not work in that case, and it would probably require using hdiutil attach -nomount to get it to be visible to DW, something like this, though I haven't had a need to try it:
hdiutil attach ddr_sda159.dmg -nomount

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: paulhagstrom on Jul 21, '07 03:17:03PM

Let me just add one thing: The reason I didn't use DW on the floppy directly is because it flipped out in various ways, spontaneously unmounting things causing the Finder to complain about unorthodox device removal. I did try that first. What I like about this recipe is that it gets as much off the disk as the drive is capable of and then I can play around with whatever recovery tools I want on the image.

One thing that I am not confident of is that DW will detect if there was an error in the middle of a file's data, my guess is that it won't. So, it's still probably necessary to treat the recovered files as being only possibly working.

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Compiled version of ddrescue for 10.4
Authored by: aangel on Oct 25, '07 01:37:42PM
To save someone (maybe you) the hassle of compiling ddrescue, I have posted a compiled version here.

It's against 10.4.10. I have not tested it against 10.5 as I don't have a copy yet.

The command I used was: sudo ddrescue -v /dev/disk2s3 /Volumes/TerraLinda/SaveMaxtor.dmg savemaxtor.log

But you will need to run diskutil list to get the correct label for your device (it's not likely to be disk2s3).

It's currently recovered 16GB and counting...

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Compiled version of ddrescue for 10.4
Authored by: atonaldenim on Jan 14, '10 03:12:02PM

Thank you very much for continuing to host this ddrescue binary for Tiger (you probably have forgotten all about it by now). I'm trying to recover a drive with many bad blocks, which seems like it will take days, and the only machine around that's not being used is running Tiger. No development tools installed to compile my own binary, but yours works perfectly. Thanks!

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Compiled version of ddrescue for 10.6
Authored by: Krioni on May 11, '13 04:42:50PM

The site also has a compiled version (1.16, compiled against Snow Leopard in April 2013). The important thing is that their download links require an account/password to avoid certain bots flagging their site. But, the account is the first line of text in their logo (case matters!) and the password is the second line of text in their logo (see their FAQ for an explanation).

Link for download page:

The Instructions on using ddrescue:

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: jammjamm on Nov 01, '07 11:28:05PM

Has anyone got this working on PPC Leopard?

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: arbee on Jan 30, '09 03:07:15AM

Your article has created a glimpse of hope. I have problem booting from the hard drive so I boot from the Mac OS X 10.4 DVD. Disk utility cannot fix the disk. How to run ddrescue on it if it does not boot. Thanks for any help and advice.
One last thing, am not too command line savvy. any additional help will be appreciated

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: JLG on Apr 27, '09 02:41:54PM
An easy way to get ddrescue installed is to install Mac Ports ( You can then open a terminal window, type "sudo port install ddrescue", and the port will install. Once that's done, you can type "sudo ddrescue" to run the program, or "sudo man ddrescue" for instructions.

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Help for ddrescue and an old SCSI Disk
Authored by: macintact on Apr 08, '10 02:51:35AM

Hello everybody,

although it's quite long ago, and if this post is still alive, I want to ask for your help on my specific problem:

1st of all I have to admit that I don't have any clue to Unix commands or working with the Terminal in OS X. All of what I typed in the Terminal was found on the Internet and then trial and error.

The specific problem was to get data of an old 40 MB SCSI HD coming from an Mac Classic. As I didn't have any real working SCSI Mac, I did the following:

Got an old SCSI Disk enclosure, got an old Orange Micro SCSI to FireWire adapter, connect it to my lovely Cube, installed all the SW I could find and spend ages in finding out how to mount that dead thing. Well, at some point it worked out and I came to this:

Last login: Mon Mar 29 18:31:40 on ttyp2
Welcome to Darwin!
Cube:~ cube$ system_profiler SPFireWireDataType

FireWire Bus:

Maximum Speed: Up to 400 Mb/sec


Manufacturer: CONNER
Model: 0x1
GUID: 0xD01600000047BE
Maximum Speed: Up to 200 Mb/sec
Connection Speed: Up to 200 Mb/sec
CP3040A-40mb-3.52.31 Unit:
Unit Software Version: 0x10483
Unit Spec ID: 0x609E
Firmware Revision: 0x120
Product Revision Level: 2.31
CP3040A-40mb-3.52.31 SBP-LUN:

Cube:~ cube$ disktool -m system_profiler SPFireWireDataType
system_profiler device will attempt to be mounted ...
***Disk Appeared ('disk0',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s1',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s2',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s3',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s4',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s5',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s6',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s7',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s8',Mountpoint = '', fsType = '', volName = '')
***Disk Appeared ('disk0s10',Mountpoint = '/', fsType = 'hfs', volName = 'Macintosh HD')
***Notifications Complete for type 1
***Disk Appeared ('disk1',Mountpoint = '', fsType = '', volName = '')
***Notifications Complete for type 1


Last login: Mon Mar 29 18:32:32 on ttyp1
Welcome to Darwin!
Cube:~ cube$ ddrescue -v /dev/disk1 MyVolImage.dmg MyVolRescue.log

About to copy 9223 PBytes from /dev/disk1 to MyVolImage.dmg
Starting positions: infile = 0 B, outfile = 0 B
Copy block size: 128 hard blocks
Hard block size: 512 bytes
Max_retries: 0
Direct: no Sparse: no Split: yes Truncate: no

Press Ctrl-C to interrupt
Initial status (read from logfile)
rescued: 0 B, errsize: 0 B, errors: 0
Current status
rescued: 0 B, errsize: 4294 MB, current rate: 0 B/s
ipos: 1534 kB, errors: 1, average rate: 0 B/s
opos: 1534 kB, time from last successful read: 2.6 d
Splitting failed blocks...


As you can see it was working now over for some days! But after the third day it seemed to start all over again.In the night I saw at " ipos:" over 97200000 kB (or something like that). I the "fs_usage" Terminal-window I seem to have lost all the old notes, and only have this now (I shortened it a lot!):

fs_usage: buffer overrun, events generated too quickly
06:36:13 RdMeta 450.067500 W ddrescue
06:36:13 access /dev/disk1 0.000168 ddrescue
06:36:13 fsync 0.000024 ddrescue
06:36:13 open MyVolRescue.log 0.003194 W ddrescue
06:36:13 fstat 0.000018 ddrescue
06:36:13 write 0.000187 ddrescue
06:36:13 close 0.000035 ddrescue
06:36:13 write 0.000043 ddrescue
06:36:13 write 0.000037 ddrescue
06:36:13 write 0.000032 ddrescue
06:36:13 write 0.000034 ddrescue
06:36:13 lseek 0.000012 ddrescue
fs_usage: buffer overrun, events generated too quickly
06:40:43 RdMeta 270.010096 W ddrescue
06:40:43 access /dev/disk1 0.000181 ddrescue
06:40:43 fsync 0.000027 ddrescue
06:40:43 open MyVolRescue.log 0.002749 W ddrescue
06:40:43 fstat 0.000016 ddrescue
06:40:43 write 0.000188 ddrescue
06:40:43 close 0.000035 ddrescue
06:40:43 write 0.000044 ddrescue
06:40:43 write 0.000035 ddrescue
06:40:43 write 0.000030 ddrescue
06:40:43 write 0.000028 ddrescue
06:40:43 lseek 0.000012 ddrescue
fs_usage: buffer overrun, events generated too quickly
06:41:13 RdMeta[async] 300.010836 W ddrescue
fs_usage: buffer overrun, events generated too quickly

The "fs_usage: buffer overrun, events generated too quickly" is coming permanently in a way and I don't really know what that means. The other things is that the DMG-File is only 8k big (and I can't mount it in the Finder), and the ddresuce log says this now:

# Rescue Logfile. Created by GNU ddrescue version 1.11
# current_pos current_status
0x0017C000 /
# pos size status
0x00000000 0x00040A00 -
0x00040A00 0x00017C00 /
0x00058600 0x00020400 -
0x00078A00 0x0003BE00 /
0x000B4800 0x00040400 -
0x000F4C00 0x0007DE00 /
0x00172A00 0x00009800 -
0x0017C200 0x00074600 /
0x001F0800 0x00000400 -
0x001F0C00 0x001FFE00 /
0x003F0A00 0x00000400 -
0x003F0E00 0x003FFE00 /
0x007F0C00 0x00000400 -
0x007F1000 0x007FFE00 /
0x00FF0E00 0x00000400 -
0x00FF1200 0x00FFFE00 /
0x01FF1000 0x00000400 -
0x01FF1400 0x01FFFE00 /
0x03FF1200 0x00000400 -
0x03FF1600 0x03FFFE00 /
0x07FF1400 0x00000400 -
0x07FF1800 0x07FFFE00 /
0x0FFF1600 0x00000400 -
0x0FFF1A00 0x0FFFFE00 /
0x1FFF1800 0x00000400 -
0x1FFF1C00 0x1FFFFE00 /
0x3FFF1A00 0x00000400 -
0x3FFF1E00 0x3FFFFE00 /
0x7FFF1C00 0x00000400 -
0x7FFF2000 0x7FFFFE00 /
0xFFFF1E00 0x00000200 -

Can somebody explain some of that stuff to me? Is it just a waste of time, because that dmg file is useless? I already contacted Antonio Diaz and he send me the link to this post. He said that I have to tell ddrescue the size of the disc with this command:

ddrescue -v -s40MiB /dev/disk1 MyVolImage.dmg MyVolRescue.log

After that I gave up for now and stopped the rescue yesterday - and I haven't tried this command. But I'm still willing to try my best with some help of yours!

Thanks for your time of reading this and hopefully you can help me with it!

Best regards,


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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: JLG on Apr 15, '10 01:40:42PM

ddrescue is a great data recovery app, but if you're not comfortable on the command line, or ddrescue isn't getting the job done for you, there are a couple of very good recovery tools that can do what ddrescue can do, and then some:

Data Rescue

Both are commercial products, but they are reasonably priced--especially when compared to the cost of data recovery services. Best of all, they're point-and-click easy.

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10.4: Recover a dead hard drive using GNU ddrescue
Authored by: woll on Aug 05, '10 09:22:05PM

I managed to rescue some of my sister-in-law's files without using any commercial software.

At first I tried using the trial versions of the available commercial software, directly accessing the crashed disk. They seemed to work and seemed to be able to find files, but they ran very slowly, so I wasn't sure that purchasing was going to be worth it. I think the problem was that the disk was really badly crashed - it looked as if only a part of the disk was accessible, so the apps tended to 'hang' after a certain point.

So, I then found this thread and tried using ddrescue to copy the crashed disk onto a working disk. I ran it a few times until it seemed to never be making any more progress. Again I never got it to completely rescue the whole disk, as the disk was really bad! Using 'tail -f ddrescue_file.log' allowed me to see that it was working and when it looked as if it wasn't going to progress much further.

Then I mounted the copy using diskutil umount ... (so that the copied disk is accessible in the next step)

Then I used Photorec ( to rescue the files from the mounted disk.

Photorec managed to find the same number of JPG files as the trial versions of the commercial software I tried, so in my case I didn't need to use the commercial software. Maybe if I let the commercial trial versions run for longer they would have got some more data off, but I suspect that the disk was too far gone.

Unfortunately, because the disk was really badly crashed, I was only able to rescue a small number of her files, but at least I got some!

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