Do BAD SECTORS get 'transferred' by Cloning?

Cannibal Corpse

Cannibal Corpse

[H]ard|Gawd
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During the past couple of days, my WD Raptor 74GB (5 years old, but not used very often) would not boot into Win7 Ult x64, and it would do so after couple of re-tries. So I decided to clone it one last time before it really stops working, (using Acronis) and it generated 'Read Error' during the process and when I aborted the clone, it reported that it might have been due to bad sectors.

Couple of days prior to this, however, I was able to produce perfect clones of this exact same drive, with no errors.

I decided to retire this drive, and use the error free clone archive, and clone it onto a new WD Raptor 150GB drive.

I ran a check disk on this drive and Win7 x64 did not report any errors.

Question: Do cloning (ghost, imaging) software transfer bad sectors onto their new destination drives? In other words, should I be concerned about my new drives 'inheriting' the original bad sectors from the source drive?

Thanks in advance!
 
Bad sectors are a physical problem and thus can't be "transferred" to another drive. However, it's possible that the data stored in a bad sector could end in up in the clone image. If it does, it likely to be corrupted. But there's so much error correction and detection going on behind the scenes, that you shouldn't have to worry about that.
 
bad sector is a physical error...
worst case is that you get garbage/nothing of the data that were in those bad sectors which probably will lead to lost data on your new drive, physically the drive will be fine though.
If your clone-image did get all/correct data of your old drive then no data would be lost...
 
Thanks for your post. Please also note that I used an 'error-free' clone archive (that I had produced couple of days prior to this incident) onto the new hard drive. Not to mention that there is no error being detected on the new drive as well.

I have all of my games already installed in a separate (E:) drive, and I use the mentioned boot drive (C:) as a medium to launch these games. (although my save files and customizations are still on the C still).

So I guess I should be fine then, eh? :)
 
I type too slow :eek:

If you're unlucky, the clone-software or/and hardware-setup might report zeros instead of the actual data that reside in the bad sectors during the clone-process and not informing the user of this, leading to files of correct size but with corrupted data...
Not sure this kind of thing can happen these days, but 10+ years ago they could (based on experience) :(
 
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I am using Acronis True Image Echo Enterprise (with Universal Restore) for my cloning. It is a server based program and an intensive program.
 
Bad sectors are added to what is known as the glist on hard drives. Once the drives firmware realizes a sector is bad, it maps the sector out and uses a backup one, and you have no access to it anymore, unless you actually attach a new controller.
 
Scotch77 said:
Bad sectors are added to what is known as the glist on hard drives. Once the drives firmware realizes a sector is bad, it maps the sector out and uses a backup one, and you have no access to it anymore, unless you actually attach a new controller.
Click to expand...

There's only so many bad sectors that can be remapped, though. And even then, the data that gets remapped isn't guaranteed to be defect-free.
 
My suggestion:

Try it. If you still have issues, it may be because some crucial file was damaged due to bad sectors. In this case, just do a repair install of windows, and the system files will be re-copied.
 
Scotch77 said:
Bad sectors are added to what is known as the glist on hard drives. Once the drives firmware realizes a sector is bad, it maps the sector out and uses a backup one, and you have no access to it anymore, unless you actually attach a new controller.
Click to expand...
G-List has nothing to do with the controller.
ryan_975 said:
There's only so many bad sectors that can be remapped, though. And even then, the data that gets remapped isn't guaranteed to be defect-free.
Click to expand...
Data doesn't get remapped. The LBA of the bad sector is mapped to a new physical address.

OP, no, bad sectors won't transfer. You won't get garbage data from them either. Hard drives are designed so that you either get good data or nothing at all. If it can't read good data from the target sector it will return a UNC error, and give you no data for that sector. Cloning utilities will either fill it with zeroes or some pattern like UNREADABLESECTOR.
 
G-List has nothing to do with the controller.
Click to expand...
He means the controller on the hard drive itself.

My question is: when the hard drive "releases" a backup sector to replace a bad one, how does it make sure that it's in the right place? Like, what if your partition is on the outside of the drive and the only available backup sector is on the inside?
 
thefreeaccount said:
He means the controller on the hard drive itself.

My question is: when the hard drive "releases" a backup sector to replace a bad one, how does it make sure that it's in the right place? Like, what if your partition is on the outside of the drive and the only available backup sector is on the inside?
Click to expand...

The sector gets remapped to a good one that's reserved. The os has no idea the sector it's calling isn't going to be the one it gets data from. The drive compares requested sectors to its list and automatically redirects to the new one. So it doesn't matter where the partition boundaries lie.
 
Martel-fs said:
G-List has nothing to do with the controller.

Data doesn't get remapped. The LBA of the bad sector is mapped to a new physical address.

OP, no, bad sectors won't transfer. You won't get garbage data from them either. Hard drives are designed so that you either get good data or nothing at all. If it can't read good data from the target sector it will return a UNC error, and give you no data for that sector. Cloning utilities will either fill it with zeroes or some pattern like UNREADABLESECTOR.
Click to expand...

YeAh I knew that... Don't know what I was thinking.
 
ryan_975 said:
The os has no idea the sector it's calling isn't going to be the one it gets data from. The drive compares requested sectors to its list and automatically redirects to the new one. So it doesn't matter where the partition boundaries lie.
Click to expand...
Wow...wouldn't that absolutely destroy performance by jumping all over the place?
 
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