Posted by Grommish on Apr 20, 2020; 3:57pm
URL: https://itus.accessinnov.com/FIRMWARE-Itus-Networks-Shield-Firmware-Upgrade-WIP-tp1726p1977.html

You can do a:  cat /init

and that is the boot script.

Down near the bottom:

       # Found an init, but is it ours?
        if [ -e ${extroot_dir}/.norwits ]
        then
           echo "Found ${extroot_dir}/init"
           echo "Firstboot flag: ${firstboot}"
           export FIRSTBOOT=${firstboot}
           echo ${SHIELD_MODE} > ${extroot_dir}/.mode
           exec switch_root ${extroot_dir} /sbin/init
        else
        # Not our external rootfs!  Time to go bubye.
        # Remove everything, then wait for the next loop to populate with our stuff.
           rm -rf ${extroot_dir}/*
        fi