System Migration Instructions:

# Temporarily mount external storage without modifying /etc/fstab. If the message
# “Information: You may need to update /etc/fstab.” appears, it can be safely ignored.

# Set the external storage to GPT format
# This document uses a TF card as an example device (/dev/mmcblk1). Please adjust
# the device name according to your actual system.

sudo parted /dev/mmcblk1 mklabel gpt

# Create a disk partition
sudo parted /dev/mmcblk1 mkpart primary 0GB 512GB   # The 512GB value can be adjusted based on actual capacity

# Set PARTUUID for external storage
sudo gdisk /dev/mmcblk1

# Execute the command and input options and GUID (PARTUUID) as follows:
nvidia@nvidia-desktop:~$ sudo gdisk /dev/mmcblk1

GPT fdisk (gdisk) version 1.0.3

Partition table scan:
MBR: protective
BSD: not present
APM: not present
GPT: present

Found valid GPT with protective MBR; using GPT.

Command (? for help): x   # enter lowercase x to enter expert mode

Expert command (? for help): c   # set GUID for the partition

Using 1

Enter the partition's new unique GUID ('R' to randomize):
82c4471a-fac6-4f3e-a829-4fb9700d1205

New GUID is 82C4471A-FAC6-4F3E-A829-4FB9700D1205

Expert command (? for help): w   # write the PARTUUID to the partition

Do you want to proceed? (Y/N): Y

# Format the disk
sudo mkfs.ext4 /dev/mmcblk1p1

Final checks complete. About to write GPT data. THIS WILL OVERWRITE EXISTING PARTITIONS!!

# Confirm with uppercase Y to proceed with writing
OK; writing new GPT partition table to /dev/mmcblk1.
The operation has completed successfully.

# At this point, the PARTUUID has been successfully set.

nvidia@nvidia-desktop:~$

# Verify PARTUUID
sudo blkid /dev/mmcblk1p1

# If the following appears, the configuration is successful:
# PARTUUID="82c4471a-fac6-4f3e-a829-4fb9700d1205"

# Mount the disk to /mnt
sudo mount /dev/mmcblk1p1 /mnt

# Copy all system files to the mounted path. Ensure the disk is mounted before running.
sudo rsync -axHAWX --numeric-ids --info=progress2 / /mnt

# This completes disk cloning. If migrating additional disks, repeat the above steps.

# For first-time system migration, perform the following in the x86 host flashing environment:

cd /Linux_for_Tegra/bootloader/

echo 82c4471a-fac6-4f3e-a829-4fb9700d1205 > l4t-rootfs-uuid.txt
echo 82c4471a-fac6-4f3e-a829-4fb9700d1205 > l4t-rootfs-uuid.txt_ext

# Put the Jetson device into recovery mode

# Flash the boot partition using the following command:
cd /Linux_for_Tegra/
sudo ./flash.sh external

# Wait for flashing to complete