Once booted, make sure no partitions are mounted from the source hard drive disk. You can boot from a live cd or USB pen drive. Making disk image with dd using live CD/DVD or USB pen drive To clone /dev/sdc1 to /dev/sdd1 with dd and create an image, enter: How to clone a partition and make disk image with dd

sync : Add input blocks with zeroes if there were any read errors, so data offsets stay in sync.

conv=noerror : Tell dd to continue operation, ignoring all read errors.

# dd if=/dev/ada0 of=/dev/adb0 bs=64K conv=noerror,sync In this example, I am going to clone /dev/ada0 (250G) to /dev/adb0 (250G) in FreeBSD and make an image using dd. # dd if=/dev/sdc of=/dev/sdd bs=64K conv=noerror,sync To clone /dev/sdc (250G) to /dev/sdd (250G) in Linux, enter: The syntax is as follow to make disk image with dd:ĭd if=/dev/input/DEVICE-HERE of=/dev/OUTPUT/DEVICE-HERE bs=64K conv=noerror,sync However, if you have multiple disks, it is possible to do it online. Typically we boot from a live USB or DVD and create disk images. Remember the input file order ( if=) and output file ( of=). You should be very careful when using the dd command it can destroy data. The nixCraft or author is not responsible for data loss. WARNING! These examples may crash your computer if executed.

Blank floppy disk image creator