I intend to use Odroid UX4, while using the boot device a USB 3 attached HDD. Downside is - it has no built in bios or anything, it just boots everything that is in the SD card slot.
Perfectly working scenario:
1. Starts the computer
2. GRUB starts searching all the connected devices and provides boot options
Scenario that I can easily make work, but would like to avoid:
1. Automatic boot to SD card
2. SD card has a script that updates grub with all the connected devices
3. Reboot
4. GRUB shows all available options
A perfect scenario to fix this would be a dynamic GRUB that gets updated on every device on boot.
Similar things I've found: http://www.supergrubdisk.org/super-grub2-disk/
Did not test this thing, thought someone would have good ideas or ways to better implement this.