[SOLVED]
I’m trying to install UmbrelOS on a CyberGeek Nano A1 Mini Desktop Computer, Intel 12th Alder Lake N100 (up to 3.4GHz), Mini PC 16GB RAM 2TB SSD. I have disabled secure boot, switched to legacy, and moved the USB to boot priority. The Cybergeek logo displays, then the GRUB boot manager starts. All messages are green “OK”, and then the HDMI signal stops. The last message before the monitor loses signal is:
OK ] Finished systemd-update-utmp-runlevel[]ervice -- Record Runlevel Change in UTMP.
(the is a non-displaying character that looks like a square)
edit 1: More info. I can use the same process and USB drive to install Ubuntu Server (also headless) and it works. I noticed during the successful Ubuntu GRUB boot, around similar output to the failed UmbrelOS GRUB messages, the screen lost signal for a second or two and then turned back on with a higher resolution (GRUB output and console text was smaller).
Ubuntu Server can install fine using the same USB, monitor, and PC. So… anyone know tips for updating the GRUB config on the ISO?
edit 2, the solution:
The ISO’s /boot/grub/grub.cfg needs nomodeset vga=normal fbcon=font:VGA8x16 added to this line
linux /vmlinuz root=LABEL=UMBRELINSTALLER ro quiet loglevel=0 nomodeset vga=normal fbcon=font:VGA8x16
I’m on linux, so the steps are sorta like this:
- mount the ISO on a loopback
- copy the contents to a read/write dir
- edit the grub.cfg file
- repack the ISO but make sure you set the same label as in the grub.cfg like with this command
mkisofs -o ~/umbrelos-fixed.iso -V UMBRELINSTALLER -J -R -l -D -allow-limited-size .
And boom this fixed it. I created a GitHub issue, as per the contributing guidelines.
Also, Ventoy is a handy tool for this.