Cloning anomaly: Lost space on destination drive
I have a 2 TB WD Black data drive that's quite old; I decided to replace it with an identical drive and clone the data from the old drive to the new.
Everything seemed to go fine, but when it was complete I looked at both drives (source and destination) using WinDirStat, which I use a lot.
It showed that the data was identical, but the free space for destination drive was reported as 33 GB lower.
The partition sizes are identical and there are no additional partitions on either drive.
33 GB is not a lot these days, but I think this is very weird.
One point that may or may not be relevant: CrystalDiskInfo was reporting uncorrectable sector counts of 200/current 200/worst for the source drive.
Any ideas as to where the 33 GB went?
Thanks, for your reply Ian.
They are both WD Black, but definitely different model and firmware numbers.
The source is from 2012; the destination is from Jan 2020.
I reformatted the destination and am backing up the files from the source to the destination right now. I want to see if anything changes.
Hopefully the problem will not reappear with the new clone.
The 8 years difference between manufacture dates suggest there could be physical differences between the drives, in particularly the number of platters, but I cannot see how this would result in a large difference in capacity.
I assume you checked in DiskManagement that the entire diskspace was used when doing the clone:
You can see in my case that Disk 1 has 23.29 GB unallocated - this is because I used Samsung Magician to overprovision the SSD. For the other two drives shown there is no unallocated space.
Ian
Hello Ian, Yes, I did check Disk Management. They each had one partition and the sizes were very close.
Source (old drive) is shown as 1863.01 GB.
Destination (new drive) is shown as 1862.89.
Thanks for the information. I must say I have no idea what is going on.
Ian
Everything seemed to go fine, but when it was complete I looked at both drives (source and destination) using WinDirStat, which I use a lot.
It showed that the data was identical, but the free space for destination drive was reported as 33 GB lower.
Did you drill down into the WinDirStat reports to see where the 33GB was on the original drive?
If all the actual data is identical, then this could just be an issue with the free space map on the original drive which was reporting an inaccurate / incorrect free space value which is corrected on the target drive.
If both drive are still available, you could do a direct comparison between them using a file / folder synchronisation tool to see what is flagged as being different?
>>Did you drill down into the WinDirStat reports to see where the 33GB was on the original drive?
The math for the source drive made sense: That was showing what should have been the correct free space available.
The math for the destination drive did not make sense: WinDirStat sometimes labels a few GB here and there as "unknown," but on the destination that was zero. I went through it line by line and the 33GB could not be accounted for.
I reformatted the new (destination) drive and backed up the files to that using my usual file backup program (Cobian). Once the files were there the free space was identical to the source drive. Weird.
Strange is the word here! The good news is that the new drive is as it should be!
Agreed! It's brand new drive. Haven't had a DOA WD in years.