Create image of hard drive sector by sector

Create image of hard drive sector by sector how to#
Create image of hard drive sector by sector Pc#

P primary (0 primary, 0 extended, 4 free)Д® extended (container for logical partitions)ДЇirst sector (2048-7553023, default 2048): enter Welcome to fdisk (util-linux 2.27.1).Д¬hanges will remain in memory only, until you decide to write them.Д«e careful before using the write command.Дevice does not contain a recognized partition table.Д¬reated a new DOS disklabel with disk identifier 0x55ecee0c.Д¬reated a new DOS disklabel with disk identifier 0xe648bbde. The user commands are shown in bold and enter is used to show where the default value was accepted by pressing enter key.

Create image of hard drive sector by sector how to#

The following commands show how to create one bootable 10 megabyte FAT partition and second partition for data (e.g. # -u give sizes in sectors instead of cylinders Note that the script first seeks to SECTORS-1 and then writes one sector worth of data, making the file size match SECTORS. The script above creates a file that is 7553024b * 512b = 3,6 GiB in size. # Create zero-file to represent the eMMC (needed for fdisk)Дd if=/dev/zero of=mem_file seek=$((SECTORS - 1)) bs=$SECTOR_SIZE count=1 Instead of actually writing gigabytes of zeros to a file, it is possible to seek to large address and only write a little. There is a simple trick to create large files practically instantaneously. These values may be different between manufacturers so refer to the memory datasheet.

As an example, lets assume an eMMC chip with 7553024 sectors and 512 byte sector size. The file size needs to match the mass storage device size so the fdiskВ utility can create correct partition sizes. Instead this post focuses on how to create one to a file.ДЇirst, a file needs to be created to represent the mass memory. The details and internal structure of the MBR will not be covered here since there already is a comprehensive Wikipedia articleВ available. This special sector is called master boot record (MBR). The partitioning information is stored in a special sector in the very beginningВ (address zero) of the mass storage device.

Create image of hard drive sector by sector Pc#

This can be the case with embedded MMC (eMMC) memories which are soldered directly to the device and cannot be connected to a PC for partitioning. However, with embedded devices it is sometimes more practical to write the partition tableВ to a file instead of directly writing it to the memory device. Usually when working with USB thumb drives, memory cards and hard drives, the partitioning can be easily done just by plugging them to a Linux (or Windows) PC and using a partitioning application such as fdisk.