Solved Partitioning question

[teckneeculler]

This is very possibly a dumb question, but here goes.
I have a 2TB drive that went bad a few months back.
I've since tried to recover its data but haven't had much luck.
I've run HDD Regenerator on the drive and seem to have established that the damaged sectors are clustered at the start and end of the drive.

The drive has only one partition. It's occurred to me that if I could set up two more partitions - one at the beginning of the drive and one at the end, encompassing the bad sectors, of which I've recorded their extents, I might be able to recover data from the center area of the drive, which doesn't seem to be damaged.

It would look something like this:
BBBBBBBBBBBBBBBBBBBBBBBBBBB GGGGGGGGGGGGGGGGGGGGGGGGGGG GBBBBBBBBBBBBBBBBBBBBBBBBBB
....with the the first lot of B's (bad) and the second lot of B's being partitions 2 and 3, while the G's (good) remain in the original partition 1.

What do you think?

Being an ex-builder, it sounds logical to me, LOL, but there's probably a reason why it wouldn't work.

 

[Paul Black]

Hi teckneeculler,

I've since tried to recover its data but haven't had much luck.

I don't know if this will help ...

Win 7 System Recovery Options - Linux LIVE DVD Or USB

You can create a Linux Live DVD or USB [this means that the Linux OS runs directly from the DVD or USB and not the HDD because it doesn't need installation]. This will read the HDD information which is inaccessible through Windows directly from the controller and is often a better solution in these types of situations. Another advantage of this is that you will have less activity on your HDD while you are trying to access it to retrieve [look at] the files.

Download the Linux ISO [I have used Linux Mint for this example] from here => Linux Mint.

Now burn the ISO [you can't just copy and paste it because it won't work] to a DVD or USB and boot it.

Nothing will be installed to your HDD unless you specifically tell it to. You can now retrieve [look at] the contents of the HDD from within Linux. When you have finished and want to go back into Windows, just remove the DVD or USB, then Shutdown and Restart the computer.

Win 7 System Recovery Options - Linux LIVE DVD Or USB Alternative [Thanks to SIW2]

This alternative is an easier way to create a Linux Live Bootable USB.

To watch the full process click the YouTube link here => Embracing Linux: Bootable USB Drive.

The Universal USB Installer can be downloaded from here => Universal-USB-Installer-1.9.8.3.

I hope this helps!

 

[Paul Black]

Hi teckneeculler,

If you can, can you do the following ...

Disk Management

Can you post a screenshot of the Disk Management please => Click Start => right-click Computer => click Manage => click Disk Management.

Screenshots And Files - Upload And Post In SevenForums

This tutorial [Published by Brink] will show you how to upload the file => Screenshots and Files - Upload and Post in SevenForums.

I hope this helps!

 

[samuria]

The problem is a drive has hidden tracks which as it finds bad blocks it remaps so once you see bad blocks there are actual lots
In theory your idea would work if you get the right parition but as the drive is faulty it cant be relied on and more trouble than its worth

 

[file3456]

I did precisely that many years ago with a bad drive. But in this case I partitioned around the bad area using the good area. So with what you said there it's worth a shot, but it may or may not work. Also, I ran HDD Regenerator multiple times because it kept fixing cluster after cluster or what ever it was. After I ran HDD Regenerator several times I was able to recover most but not all data.

This is why you should clone your drive to an external drive all the time. This is what I do now using AOMEI Backupper.

 

[SIW2]

seem to have established that the damaged sectors are clustered at the start and end of the drive.

The drive has only one partition. It's occurred to me that if I could set up two more partitions - one at the beginning of the drive and one at the end, encompassing the bad sectors, of which I've recorded their extents, I might be able to recover data from the center area of the drive, which doesn't seem to be damaged.

What do you think?

Being an ex-builder, it sounds logical to me, LOL, but there's probably a reason why it wouldn't work.

yes, it is worth a try. I have done similar with some success.

 

[dg1261]

It would look something like this:
BBBBBBBBBBBBBBBBBBBBBBBBBBB GGGGGGGGGGGGGGGGGGGGGGGGGGG GBBBBBBBBBBBBBBBBBBBBBBBBBB
....with the the first lot of B's (bad) and the second lot of B's being partitions 2 and 3, while the G's (good) remain in the original partition 1.

Since your intent is to "recover data from the center area of the drive", I'm puzzled how you would accomplish this. Creating three partitions is certainly doable if you were going to wipe the partition table and start over, but not if you need to preserve what's already there. The good sectors would become partition 2, they do not remain as "original partition 1".

The problem is all those good sectors cannot remain untouched and still be a readable partition. The partition boot sector (which is now at the beginning of the B's) would have to be rebuilt on the first G, and the MFT (which is now who knows where) would have to be relocated into the middle of those G's. Both of those requirements mean something is going to get overwritten in the G's.

Furthermore, even if a file is otherwise recoverable (i.e., resides completely within the G's), how would you find it? How would a new MFT know where the existing files are? Each file's original MFT entry would be referenced to the original single partition's boot sector, so it would be useless to copy that MFT entry to a new MFT (rebuilt somewhere in the G's), even if you could.

Incidentally, for your purposes you don't need to create new partitions at the beginning and end, you would merely need to change the beginning and ending sectors of the existing single partition -- IOW, resize it smaller from the back end and move it in its entirety away from the front edge of the disk.

That would have the effect of readjusting the MFT and building a new partition boot sector within the G's (which you surely wouldn't be able to do manually), but the question is whether any current partition management utility would do it. Most of the utilities I've seen seem to do an integrity check on the file system before they'll take any action, so they might balk at performing the tasks you want.

If your intent is to save as much as possible, I think your best bet is to use some sort of file recovery software to try and read the existing MFT and copy as many files as you can to another drive. If you then want to try and reformat/reuse the disk (though I don't know why you would), you could wipe the partition table and create a new, smaller partition in the middle of the disk.

 

[SIW2]

change the beginning and ending sectors of the existing single partition

IIrc that is what I did, rather than creating extra partitions. It was a some years ago, and worked quite well as I remember.

I think your best bet is to use some sort of file recovery software to try and read the existing MFT and copy as many files as you can to another drive. DG

The OP has already tried that.

I've since tried to recover its data but haven't had much luck.teckneeculler

Can't remember for certain what software I used - could have been minitool power data recovery edition 6.5

 

[teckneeculler]

Guys, thanks very much for your input.

My apologies, I should have said that I wasn't desperate to recover the data.
My interest is more academic than anything else. Like - could the partitioning that I described be done?

Incidentally, I believe DG1261 thought I was intending to create three partitions. Not so - I said two.

This is because, according to my limited understanding of the process, creating a partition in the - let's say, center of the drive, where all the good stuff may still remain - would unflag any data in that area, making it even more difficult to recover.

What I asked was, if I created a partition on each side of the bad sectors, could I then enter the middle partition - which is the remaining chunk of the original single partition - and recover files?

SIW2 and F22SimPilot got the picture - thanks, guys.

SIW2: This is the same hard drive we had recent dialogue about. I copied it to a new drive, using a Linux-based DDRescue app, instructing it NOT to retry recovering bad sectors, because it would have added months to an already lengthy recovery forecast.

It crashed after 3-4 days so I loaded the copied drive into my computer, and was gob-smacked to find that everything seemed to have copied. Couldn't believe it! However, a closer examination revealed that all of the copied information - folders, docs, apps, zip-files, webpages etc - consisted entirely of zeros, not a 1 in the whole 2TB. Sheesh. Oddly, even the sizes were being reported as identical to the originals.

Could have had something to do with my telling DDRescue not to re-try unsuccessful attempts.

Anyway, I don't really need the undamaged data, , I'm just curious as to whether my idea would work.

Sounds like it might, I'll give it a go.

 

[dg1261]

Incidentally, I believe DG1261 thought I was intending to create three partitions. Not so - I said two.

The drive has only one partition. It's occurred to me that if I could set up two more partitions - one at the beginning of the drive and one at the end ...

Perhaps a difference in semantics? I was talking about modifying the disk to have three partitions -- and you did say "one" plus "two more". Perhaps you misinterpreted my post as meaning to create three more than you already have?

The middle sectors (the G's) cannot remain untouched as "the original partition". Those sectors would have to be modified with a new partition boot sector and a new MFT. And once you lose the original MFT I don't know how you'd populate a new MFT with "pre-existing files", so to speak, to save the previous data in the G's.

I've been hacking boot sectors, partition tables and FATs (though not MFTs) manually with sector editors for 35 years, yet I can't envision how it would be accomplished. Maybe there's something I don't know about MFTs, but if you try it I'd be interested in your results.

 

[teckneeculler]

DG1261: Thanks, sounds like my idea won't work after all.No prob.

You said earlier, 'Incidentally, for your purposes you don't need to create new partitions at the beginning and end, you would merely need to change the beginning and ending sectors of the existing single partition -- IOW, resize it smaller from the back end and move it in its entirety away from the front edge of the disk.'

That sounds like a plan, I'll try that. Is there an app that will quickly identify the extent of the bad sectors? HDDRegen worked OK but it took about a month.

 

[dg1261]

Is there an app that will quickly identify the extent of the bad sectors?

I use HDAT2 for that purpose, though there are probably others as well. HDAT2 makes a half-hearted attempt to recover bad sectors, so doesn't waste too much time on them before moving on. It might be quicker than most other utilities at surveying the entire disk and letting you know where the bad sectors are.

Note HDAT2 is a DOS-based utility, so may be incompatible with some of the newest PCs that don't support that. See the HDAT2 website for more info.

 

[teckneeculler]

Thanks again, I've downloaded the app and I'll try it on the duff hdd.
Cheers.