Updating TFTP Root Partion's PARTUUID for Network Booting a Pi 4

update-partition-PARTUUID.sh

# Mount the NFS Folder
NFS_DIR="$(mktemp -d)"
sudo mount ${NFS_IP}:${NFS_ROOT_PATH} ${NFS_DIR}

# Update the PARTUUID
sudo sed -i -r -E \
  "s@(.*root=PARTUUID=)[A-Za-z0-9-]+(.*)@\1${ISCSI_ROOT_PARTUUID}\2@" \
  ${NFS_DIR}/cmdline.txt
  
# Unmount the NFS Folder
sudo umount ${NFS_DIR}