Hi, I need help with something very important that I'm very new at doing that I'd rather not try manually with a hex editor first if I can have it done for me and see if it works.
Here's the situation... I have an old computer with a hard disk that got knocked over and the heads must have crashed onto the platter because it suddenly made about 1400 bad sectors in a single spot near the beginning of the hard drive, right amidst the old windows XP program files. The MBR is fine, the $MFT is fine (and its backup is far from the bad sectors) and the boot sector can be repaired.
What I have:
- Source drive with bad sectors
- Replacement drive of the exact same make and model (after I image the OS from that), which is error free as well.
- Original drive of this computer which was removed after cloning it to a new drive... saved just in case of this situation
- UBCD 5.5, which I'm going to use Parted Magic from to use ddrescue
What I want to do:
I read that ddrescue within Parted Magic can fully clone a hard drive with bad sectors, either to an image file or directly to disk, and it makes a mapfile to map where all the good and bad sectors are... and you can even make it mark bad sectors with custom text, like BADSECTOR at the start of the unreadable sector when it writes to the cloned disk / image.
>>> I want to use this specifically because it also says that it can use the mapfile and an undamaged backup copy of a disk to replace the bad sectors from the backup copy. <<<
So.... in order, I want to...
1. Use ddrescue to clone my damaged drive (in reverse) to the replacement drive of the same make and model, have it store the mapfile to my USB drive (I think I understand how to do this already thanks to a good tutorial page)
2. unhook the damaged drive and hook up the original hard drive my damaged drive was cloned from
3. The part I am not sure how to do... use ddrescue with the mapfile to copy from the original drive all sectors that were marked bad during the cloning process... and ONLY those sectors.
And also, on step 1, if I can do this while cloning, have it write BADSECTOR to the cloned replacement drive at every bad sector to make it easy to find the bad sectors with a hex editor.
The reason I want to try this first is because, before I cloned the original drive to this now damaged drive, I believe I used a program to defrag the original drive. I checked a number of random areas, especially around many bad sectors, on both this damaged drive and the original drive, and it appears that most, if not all the data that got damaged is still the exact same data in the same place on both drives, since I never did anything to windows after I cloned the original drive.
I wanted to try cloning the undamaged sectors from the original drive onto the bad sectors after I clone the damaged drive and see if my drive is whole again, and then probably try a system restore just in case so it replaces all the drivers and programs and stuff from its backups... the latest I believe is far from the bad sectors as well. Also doing a repair of the boot sector before booting to windows, just in case.
I also wanted to have it write BADSECTOR to the start of every bad sector so I can check to be sure it filled them in, but also want to know how just in case this doesn't work and I can go and look at the discrepencies in the PTS Disk Editor between both drives.
Sorry this sounds complex... the short of it is I don';t know how to make it write BADSECTOR at bad sectors to the new drive while coning the bad drive so I don't have to run the bad drive again... and more importantly, I don't know how to make ddrescue use the mapfile to clone only sectors marked bad during cloning from a good backup to the clone with the bad sector data holes.