Using DD: Image file becomes larger than original SFS drive from SC101

rodyz · 08-11-2009, 06:27 PM

Hi all,

the card of one of my drives in my Netgear SC101 crashed. The drive repeated to start unlimitedly, which I could hear. I took the card of the second one, and the drive seemed to run successfully, but did not show up with the SC101 client. Removing the drive and connecting by USB had also no success under XP, but with Knoppix Live CD I could see the drive as sdb device (with no directory, which I regarded as normal as SC101 has the proprietary file system SFS). So I give it a try to run DD (which took several days), but I stopped the process unfinished, when I recognized that the created disk image became larger (320GB) than the original drive (280GB).

I used the command dd if=/dev/sdb of=path/to/image.

Does anyone have an idea, what happened and what to change to be eventually more successfully saving my mp3-collection?

TIA Peter Rodyz

Meson · 08-12-2009, 11:08 AM

What do you mean when you say, "the card?" Do you mean the circuit board on the hard drive itself? Maybe the malfunctioning part is still being used by the drive. To speed things up you can use a different block size.

Code:

dd if=/dev/sdb of=path/to/image bs=1024

Also, you may either want to pipe your image through gzip (if you do this, you should zero fill your free space first), or use CloneZilla. Clonezilla will copy on a file-by-file basis and not waste your time with empty space.

rodyz · 08-13-2009, 04:41 PM

Meson: Yes, I mean the circuit board on the HDD. It is functioning, it was taken from the 2nd identical HDD of the SC101.

I can't copy on file-by-file basis, because of the proprietary file system of the SC101. Therefore I wanted a disc dump. I still wonder why the image grew bigger than the capacity of the HDD.