dd if=/dev/sda of=/dev/sdb bs=512M conv=sync,noerror,notrunc status=progress dd if=/dev/sda of=/dev/sdb bs=512 conv=sync,noerror,notrunc status=progress dd if=/dev/sda of=/dev/sdb bs=8192 conv=sync,noerror,notrunc status=progress dd if=/dev/sda of=/dev/sdb bs=8K conv=sync,noerror,notrunc status=progress dd if=/dev/sda of=/dev/sdb bs=16384 conv=sync,noerror,notrunc status=progress dd if=/dev/sda of=/dev/sdb bs=16K conv=sync,noerror,notrunc status=progress