Difference between revisions of "Dd"

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(Added dd command options.)
(Added warnings about using command line arguments correctly)
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   dd if=/dev/hda of=mybigfile.img bs=65536 conv=noerror,sync
 
   dd if=/dev/hda of=mybigfile.img bs=65536 conv=noerror,sync
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==Cautions==
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Use extreme care when typing the command line for this program. Reversing the <tt>if</tt> and <tt>of</tt> flags will cause the computer to erase your evidence!

Revision as of 13:34, 5 November 2005

dd, sometimes called GNUdd, is the oldest of the imaging tools currently in use. A command line program that has been ported to many operating systems, dd uses a complex series of flags to allow the user to image or write data from and to raw image files. There are a few forks of dd for forensic purposes including dcfldd, dccidd, a Microsoft Windows version that supports reading Physical Memory.


When using dd, be sure to specify a proper "conversion" that will ignore bad blocks. You can also improve imaging performance by specifying a blocksize that is larger than the default of 512 bytes.

Here is a common dd command:

  dd if=/dev/hda of=mybigfile.img bs=65536 conv=noerror,sync

Cautions

Use extreme care when typing the command line for this program. Reversing the if and of flags will cause the computer to erase your evidence!