How to Clone a Hard Drive With Bad Sectors Using ddrescue

[lcoughey]

Yeah...I wouldn't bother with the retries until you first get the good sectors cloned. Just be sure that your data is not worth a few hundred bucks, because it will likely cost a lot more after you fight with it and possibly kill it for good.

 

[NNenov]

Ok, thanks.
Just to be clear, can I partition my 2TB drive (NewDrive) into one 510GB partition (A) and one 1500GB partition(B)?


- so i do a 1 pass image of OldDrive to NewDrive partition B, where I also store the log file;
- then I try the same DDrescue command but with a 3 pass trigger to the same destination (NewDrive partition B) pointing to same log file location?
will that then try to do a more complete restoration to the same image file?
-Now I have the image file processed with additional passes (if the drive dies while doing the additional passes, ill the image file be compromised in any way?) on NewDrive partition B, can I try and fix it any more, how can I check its health?
- My final question, if I used partitions, will I be able to read from partition B and write to partition A simultaneously as I try to write the image to the partition?
Thanks again!

edit- sorry, did you mean i can clone directly to the new drive, and then do it again, using multiple passes? so there's no need for any partitions or making an image file at all?

 

[Jared]

If you're going to clone to an image file rather than to a drive, you can certainly use just one drive for the destination data and the log file. There wouldn't even be any need to create two partitions.

However, if you want to make a full clone drive, then your plan is somewhat flawed. Your original disk contains its own partition table. So if you create two partitions then start imaging to the disk (e.g. /dev/sda to /dev/sdb ) it's going to immediately overwrite the partition table you created with the one from the original drive. If clone drive to partition (e.g. /dev/sda1 to /dev/sdb ) then you'll have a partition table at the partition starting sector instead of a file system start, and it's not going to be recognized by the system. If the drive you are trying to ddrescue is able to mount you could however go partition to partition (e.g. /dev/sda1 to /dev/sdb1 ) and then store the log file on a separate partition as you suggest.

 

[NNenov]

Ah, so you cannot clone a drive to a partition, treating the partition as a unique drive.. e.g. cannot do /dev/sda to /dev/sdb1 I think that makes sense.
The old/damaged drive does not consist of any partitions, just one space
So considering I have just two drives, the old 500gb and the new 2tb, I should just do a direct clone of the old drive to the new, storing the log on the boot usb stick? Once the cloning is complete, I can run the command again to do multiple passes without any need for an image file? then I can open disk manager in windows and create a new partition for the rest of the empty space on the new disk?

 

[jol]

I think you have 1 mistake, when you use -r3 and a bad sector gets hit, IIRC it doesn't try 3 times right the way
Its been done in the end, when finished with the good sectors. (again, not sure)

 

[Jared]

Ah, so you cannot clone a drive to a partition, treating the partition as a unique drive.. e.g. cannot do /dev/sda to /dev/sdb1 I think that makes sense.
The old/damaged drive does not consist of any partitions, just one space
So considering I have just two drives, the old 500gb and the new 2tb, I should just do a direct clone of the old drive to the new, storing the log on the boot usb stick? Once the cloning is complete, I can run the command again to do multiple passes without any need for an image file? then I can open disk manager in windows and create a new partition for the rest of the empty space on the new disk?

You could clone a drive to a partition if you really want to. Ddrescue will certainly do it. But, no OS is going to recognize it, and even most data recovery software will be confused by it. I suppose if you really wanted to do that you could then use R-Studio and create a custom region of the partition so you can treat it like a separate disk, but then it'd be easier to just use an image file for that purpose.

 

[NNenov]

Thank you Jared for your help. The drive is not an OS drive, but it did contain my windows documents and the majority of installed windows applications and other linked folders.

I ended up using a boot CD with knoppix and a usb stick to store the logfile. I did a direct clone from the broken drive to the new drive.
I have posted in the data recovery forum here the screenshot of my logfile, would you mind having a look at the post and let me know what you think?
feedback-on-logfile-created-by-ddrescue-t1625.html

Thanks again!

 

[Jared]

I don't think you're understanding, I'm not just saying it's not going to boot if you image a whole drive to a partition, I'm saying the OS (any OS) isn't going to even recognize what the heck it is. You won't be able to browse the file system or anything. The problem will be that it's expecting the beginning of a file system, and instead will be finding a whole other partition table there. So it'll probably just ask you if you want to format the disk.

Anyway, glad you were able to get it done.

 

[bigterd]

Seems the best approach is to write images, make copies, experiment with files system checks, etc and mount offset loops... Way less hardware needed and headaches needed...



Sent from my S-Off'ed HTC One...

 

[NNenov]

I have to agree, cloning was unsuccessful due to the drive turning off/needing power cycle if trying to access the first %8 of the drive, so the new cloned drive wouldnt mount/boot. I had to format the new disk and write an image file instead. Hopefully I can at least recover something from this new .dd file trying to read about/understand testDisk now