Install ddrescue

sudo port install ddrescue

If you don’t have ports installed, then I would recommend doing some web searching on how to install ddrescue.

Identify Disk:

identify the “name” of the disk you want to “image” .

diskutil list

Example:

Macbook:~ bob$ diskutil list
 /dev/disk0
 #:                       TYPE NAME                    SIZE       IDENTIFIER
 0:      GUID_partition_scheme                        *200.1 GB   disk0
 1:                        EFI EFI                     204.2 MB   disk0s1
 2:                  Apple_HFS Mac                     199.7 GB   disk0s2
 3:                 Apple_Boot Recovery HD             641.1 MB   disk0s3
 /dev/disk1
 #:                       TYPE NAME                    SIZE       IDENTIFIER
 0:     FDisk_partition_scheme                        *250.8 GB   disk1
 1:               Windows_NTFS Windows Hard Drive      250.8 GB   disk1s1
 Macbook:~ bob$

The first disk “disk0” is the OS X System disk, the second one “disk1” is an external drive, the one I want to image.

Recovery/Image command:

Change /dev/disk1s1 to your disk.  If you have multiple partitions and want to image the whole drive then just use the disk name like “/dev/disk1”  instead of  “/dev/disk1s1”.

sudo ddrescue -v /dev/disk1s1 ~/Desktop/ddrescue.dmg ddrescue.log

In the above command I am attempting to rescue data from the first partition on disk1 and send it to an image “ddrescue.dmg” on my desktop.

Now go get some coffee, lunch, etc. and it might be finished when you get back…