bad sectors on a 1 TB disk

Using TestDisk to repair the filesystem
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Posts: 4
Joined: 09 Feb 2016, 02:38

bad sectors on a 1 TB disk

#1 Post by ppchu9999 »

so I have an USB drive with FAT32 on to create the DD image target...

on a HP 1TB drive with bad sectors, NTFS.

trying to create an image.dd file, I think it only goes up to 4G in size, and cuts it off...

Not sure if there is a way to do this, telling it to use multiple DD sizes of less than 4G...


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Re: bad sectors on a 1 TB disk

#2 Post by cgrenier »

If there is nothing on the destination, the best is to overwrite the whole disk using gnu ddrescue.

Posts: 4
Joined: 09 Feb 2016, 02:38

Re: bad sectors on a 1 TB disk

#3 Post by ppchu9999 »

not sure if I have the right syntax doing ddrescue,

I am trying to do the 1st 4G or so using

ddrescue -d -r3 -s4000000k /dev/sda4 /index/image.dd

however, I could not do mount on image.dd ,

using mount -o loop,ro /index/image.dd /mnt/img under Ubuntu 15.10

Or is there a correct to take certain chunks of my disk, I am only going 3G per day, there is only 100G of real data I want to get out of this 1 TB disk, and I have a pretty good idea where the files are located..

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Joined: 14 Feb 2016, 06:47

Re: bad sectors on a 1 TB disk

#4 Post by oldefoxx »

dd does cloning, meaning it expects everything to match up on a sector-by-sector basis. If you just waht to copy files, a much better choice is rsync, available for most operating systems. It maintains the most recent update if two files have the same name in the same folder for synchronization purposes. It also allows the source or destination to be networked rather thsn local. And it allows multiple selections for include or exclude, and these can be set up as lists if you like.