ddRescue is a Linux data recovery command that has a wide variety of uses to copy data and files from damaged and faulty hard drives. Run from the command line, ddrescue allows a high amount of flexibility in copying data and is widely used by troubleshooters and Linux administrators when they encounter problems on Linux systems (see the Wikipedia entry here https://en.wikipedia.org/wiki/Ddrescue). Here’s a recent question I received:
“I’ve had a RAID0 array on my QNAP NAS and one of the drives recently started showing bad sectors.
I bought a new drive (planning to walk away from RAID0) but while copying files across the drive failed me completely.
I’ve tried various ways to create an image from the “bad” drive (including ddrescue) but I’ve had little success.
The drive doesn’t make any weird sounds but this sounds like a hardware failure.
I was wondering if you handle cases like these and whether I could get a quote.”
Bad sectors are areas of your hard drive that your computer is no longer able to read. This is usually due to the magnetic signal not being strong enough for the read write heads to interpret correctly. All mechanical hard drives develop bad sectors and the older the drive the more bad sectors it will have. For those of you wanting a more thorough explanation of bad sectors I recommend this Wikipedia link https://en.wikipedia.org/wiki/Bad_sector.
Bad sectors are a problem that is not related to your data, rather to the way it is stored – your hard drive is not able to store information correctly on areas of the hard disk that have these bad sectors. The computer can’t write to these areas and can no longer read from these areas with success, therefore, running a software program to try and copy information from areas of the drive that have gone bad is not going to work.
Programs such as repair utilities, data recovery programs of copying programs like ddrescue will all fail for the simple reason that they are unable to read data from the bad sectors of a hard drive. The only way to successfully read data from bad sectors is to use a hardware solution that is not reliant on software. Data recovery companies such as http://www.datlabsdatarecovery.co.uk/ should be able to help you.