Diskpatch hangs rebuilding partition table and boot sector

[wire_weaver]

OK, so I have managed to progress in my investigation using the superb utility MHDD.    It identified unreadable sectors for me.  In short I am looking for a way to clone all of the HDD less the  bad sectors.    The reason the other programs I tried kept hanging (including Diskpatch) is that for some strange reason the HDD becomes unresponsive once a bad sector is read and then requires power cycling to re-establish comms with it.  Basically the BIOS or Operating system returns the disk "Not Ready" error message (akin to if a CD or floppy was not inserted into its drive), and the only way to clear this error is to power cycle the drive/laptop.

Fortunately MHDD was also able to read the SMART data from the HDD

Using MHDD I was able to identify unreadable/bad sectors in the range from LBA 230465 to about 168,000,000.  After that (up to 973,776,168) there were no errors and all read delays were <3ms. Between LBA=0 and 230465 there were progressively more read delays, some up to 500ms.

Using MHDD, here is the SMART log file output:

     

HDD: ST9500325AS; FW: 0003DEM1; SN: 5VE.....
      --------------------------------------------------------
      Name Val Worst Raw
      Att # 1 : Read error rate : 95 72 115908760
      Att # 3 : Spin up time : 97 97 0
      Att # 4 : Number of spin-up times : 96 96 4305
      Att # 5 : Reallocated sectors count : 95 95 103
      Att # 7 : Seek error rate : 79 60 93308185
      Att # 9 : Power-on time : 95 95 4847
      Att # 10 : Spin-up retries : 100 100 0
      Att # 12 : Start/stop count : 96 96 4281
      Att # 184 : Unknown : 100 100 0
      Att # 187 : Unknown : 1 1 21751
      Att # 188 : Unknown : 100 99 196618
      Att # 189 : Unknown : 100 100 0
      Att # 190 : Unknown : 76 45 404160536
      Att # 191 : Unknown : 100 100 1341
      Att # 192 : Power-off retract count : 100 100 54
      Att # 193 : Load/unload cycle count : 68 68 64791
      Att # 194 : HDA Temperature : 24 55 24
      Att # 195 : Hardware ECC recovered : 51 41 115908760
      Att # 197 : Current pending sectors : 100 100 1936
      Att # 198 : Offline scan UNC sectors : 100 100 1936
      Att # 199 : Ultra ATA CRC Error Rate : 200 200 0
      Att # 240 : Unknown : 100 253 4702
      Att # 241 : Unknown : 100 253 3950347515
      Att # 242 : Unknown : 100 253 1248635570
      Att # 254 : Unknown : 100 100 0
      

Given the large range of un-readable sectors (from 230465 to about 168,000,000), in my novice opinion it appears to me that a head is faulty.
So my plan is to clone the HDD and recover the data, but I need some S/W that will permit me to manually specify the LBA range(s) to clone because once the bad sectors are read the drive needs power cycling - so even if S/W can automatically detect then not copy bad sectors, I know it will fail/hang unless it is able to power cycle the HDD.

rgds
Peter

[Tom]

Well, DiskPatch allows you to specifiy ranges, but it will be a lengthy process. Look at the manual and the walkthroughs for details, it's all there.

[wire_weaver]

Well, DiskPatch allows you to specifiy ranges, but it will be a lengthy process. Look at the manual and the walkthroughs for details, it's all there.

Thanks Tom.  Using Diskpatch  and selecting ranges for the read-only surface scan would have taken me a lot more trial and error as Diskpatch  would hang each time it read a bad sector on my HDD.

Now I know the LBA ranges to clone, I notice that Diskpatch can allow me to specify which sectors to clone.  I can do the conversion between LBA and sector numbers, my main question is how do I 'join up' the two separated sections that I clone (either side of the bad area), or do I just leave them separated ?  I'm assuming I will then need to recreate the MBR etc. for the cloned partition.

BTW I'm also trying to use ddrescue from a linux boot CD to achieve this clone too to hedge my bets.  This route has a steeper learning curve as my unix knowledge is only fair.  It is also all cmd line driven thus taking longer.

rgds
Peter

[Tom]

my main question is how do I 'join up' the two separated sections that I clone (either side of the bad area), or do I just leave them separated ?  I'm assuming I will then need to recreate the MBR etc. for the cloned partition.

That's not possible. The "gap" should stay where it is, also in the target. Any area past the gap must be in the same place in relation to the area before the gap, or the file system won't know what's where. So you'll have to clone the entire occupied area of the source disk, gaps and all.
In addition, repairing the MBR for this particular clone action will be pretty useless; it's almost certain that this volume won't be accessible in a normal way. You will have to lift the data from the target by using something like iRecover.

[wire_weaver]

you'll have to clone the entire occupied area of the source disk, gaps and all.

Thanks again Tom.  Given my HDD is inaccessible when any program attempts to read the bad sectors, I'm going to have to clone before the bad sectors and after them and then manually edit the target's 'bad sectors' to say set them to all zeroes.

Is it going to be possible using Diskpatch to specify exactly where to write each separate set of sectors on the target when I clone each section separately ? (remember diskpatch will most likely hang when attempting to clone any of the bad section, so I must manually tell it to avoid that)

rgds
Peter

[Tom]

The smartest way to deal with that gap and zeroes is to wipe the target disk before cloning. That way you can't accidentally mess up zeroing stuff afterwards. Wiping a target disk before cloning is always good practice; that way left-over junk won't interfere with the recovery. Especially important here because of that gap.

If you know the ranges it will be quite easy to direct DiskPatch through the cloning. You'll have to do that manually though; so enter the range for the first bit (and let the clone run), ignore the gap area, then enter the range for the last bit (and again, let the clone run). So it will be two cloning actions, essentially. If you make sure DiskPatch doesn't touch the bad areas, there should be no hanging.