How to modify system.img or raw after cloned from tx2 device?

i have already cloned system.img and system.img.raw from Jeton-TX2 device…
Now, i want to modify the files in system.img, then flash to board again…
What should i do to achive that?
Thank you!

hello flyforward,

you may install QEMU utility on your host for a prerequisites.
for example,

$ sudo apt-get install qemu
$ sudo apt-get install qemu-user-static

please mount the raw image to your host machine, after that, you should also enable chroot for modification.
once complete, exit chroot and also unmount the chroot mount points, generating another new tarball for your customize rootfs.

please check below,
it show the steps for creating a custom rootfs on your host device for reference,
How to copy whole rootfs of Jetson TX2 to PC - #2 by JerryChang

you must include -r options to skip building system.img; reuse the existing one. when you restore the image via
please check Flash Script Usage for reference,

Some added notes…

system.img.raw” is the one you can mount and modify. “system.img” is faster to flash since it is a “sparse” image (think of it as “poor man’s compression”). As the system fills up with content the system.img will begin to approach the size of the system.img.raw. There is the “mksparse” tool (using “0” as the fill pattern) to create a sparse image from a raw image. Either sparse or raw will flash equally well, though smaller sparse images will be faster.

To examine or manipulate a raw image you can loopback mount it. For example, if you want to mount it on “/mnt”, and let the mount command itself apply the loopback device:

sudo mount -o loop ./system.img.raw /mnt
cd /mnt
# things...
# Before umount the device must not be in use, so:
sudo umount /mnt

The “losetup” command is performed for you with the above, but you could apply this manually:

sudo losetup --find --show ./system.img.raw
# Assuming it finds and uses "/dev/loop0":
lsblk -f /dev/loop0
sudo mount /dev/loop0 /mnt
# Explore and work on the partition at "/mnt".
sudo umount /dev/loop0
# Detach loop0 so you don't "leak" loop devices:
sudo losetup -d /dev/loop0


  • Do not flash a system.img from one release into another release.
  • If you forget the “-r” argument to, then it will overwrite your “Linux_for_Tegra/bootloader/system.img”. Use a copy or be certain you don’t flash without “-r”. It is a large file so a copy it takes a long time and a lot of space.
  • It is best to flash everything, not just the system.img. A lot of boot related content is added and not just the system.img, but the time required is very short and it guarantees it matches the release.
  • If the system.img is a non-default size, then you probably need to use the “-S size” option so that the partition fits correctly.
1 Like

Thank you for your useful solution!

Thank you for your useful solution and tips!