DD
Examples
Caution: Use dd cautiously — improper usage or entering the wrong values could inadvertently wipe, destroy, or overwrite the data on your hard drive.
dd if=/dev/sr0 of=/home/hope/exampleCD.iso bs=2048 conv=noerror,sync
Create a ISO disc image from the CD in the computer.
dd if=/dev/sda of=~/disk1.img
Create an img file of the /dev/sda hard drive. To restore that image type: dd if=disk1.img of=/dev/sda
dd if=/dev/sda of=/dev/sdb
Copy the contents from the if= drive /dev/sda to the of= drive /dev/sdb.