0

I want to create a image file that contains two partitions:

  1. 100MB FAT Boot partition that contains my kernel zImage and dtb(device tree blob) files.
  2. 900MB EXT4 Rootfs partition that contains my root file system.

Then I want to be able to flash that image file to any sdcard to boot may linux board.

How can I do this and what tools I need? (I prefer cli based tools rather than GUI)

Note: I have my kernel zImage and DTB and rootfs already and I need to make an sdcard bootable image of all of them to easily burn it on any sdcard. But for now I don't have an sdcard. I'll buy my sdcards later. first I want to have the image ready and when I buy them I'll flash the image on all of them swiftly.

0

It's an easy task! Just follow these 15 steps.

steps:

  1. Allocate a file space with fallocate -l 500M sd.img.
  2. Use fdisk(dos partition table) or gdisk(gpt(guided partition table)) to create partition table sudo fdisk sd.img.
  3. After opening fdisk, create a partition by pressing n and then press p to create a primary partition and then just press enter to leave everything by default, except the "Last sector" option. enter +100M to create a 100MB partition.
  4. Redo the third step to create the second partition.
  5. Enter w to save and exit.
  6. Create loop device of your image using sudo kpartx -av sd.img.
  7. Format the partitions sudo mkfs.fat /dev/mapper/loop0p1 and sudo mkfs.ext4 /dev/mapper/loop0p2.
  8. Create a mounting points sudo mkdir /mnt/temp_part1/ & sudo mkdir /mnt/temp_part2/.
  9. Mount the partitions sudo mount /dev/mapper/loop0p1 /mnt/temp_part1/ and sudo mount /dev/mapper/loop0p2 /mnt/temp_part2/ .
  10. copy your content into the mounting points.
  11. sync sudo sync.
  12. Unmount them sudo umount /dev/mapper/loop0p1 /mnt/temp_part1/ and sudo umount /dev/mapper/loop0p2 /mnt/temp_part2/
  13. Delete loop devices sudo kpartx -d sd.img
  14. Flash your image on your sdcard using any flasher software on any OS. I use BalenaEtcher.
  15. Enjoy your SD Card!

Your Answer

By clicking “Post Your Answer”, you agree to our terms of service, privacy policy and cookie policy

Not the answer you're looking for? Browse other questions tagged or ask your own question.