Hello igor
Sorry for hijacking this thread but i think i have the same problem.
I recently purchased an Odroid c2 and i'm new to linux. I've been using the c2 with OMV for weeks now but when i update ( attached a screenshot below ) u-boot odroidc2 from the update manager of the webgui the device never boots doesn't show on the network. I have opened an issue on the OMV forums https://forum.openmediavault.org/index.php/Thread/21632-Odroid-C2-After-update-i-loss-the-device-from-the-network-can-t-get-it-to-work-p/?postID=166970#post167045 since i thought it was an OMV problem but it's not. Please take a look and help me. Thank you in advance