When the Odroid is running, it’s got a bright flashing blue light. I found this to be very annoying, so I found a way to switch it off. You can switch it off directly by running the code:
su - echo none > /sys/class/leds/blue\:heartbeat/trigger
But for a more permanent solution, just add the second line to the file –
This file gets called by odroid-tweaks.service, which gets run at startup.