Disk cloning

Cloning an entire hard disk

From physical disk /dev/sdX to physical disk /dev/sdY

# dd if=/dev/sdX of=/dev/sdY bs=64K conv=noerror,sync

This will clone the entire drive, including the MBR (and therefore bootloader), all partitions, UUIDs, and data.

• noerror instructs dd to continue operation, ignoring all read errors. Default behavior for dd is to halt at any error.
• sync fills input blocks with zeroes if there were any read errors, so data offsets stay in sync.
• bs= sets the block size. Defaults to 512 bytes, which is the "classic" block size for hard drives since the early 1980s, but is not the most convenient. Use a bigger value, 64K or 128K. Also, please read the warning below, because there is more to this than just "block sizes" -it also influences how read errors propagate. See [1] and [2] for details and to figure out the best bs value for your use case.

https://wiki.archlinux.org/index.php/disk_cloning