Well, you are perfectly right, I was afraid I would loose my config and after testing that, I can confirm that without the USB key, the system boots on CasaOS which is the default OS that comes with the ZimaBoard.
Also, after rebooting it but this time with the USB key, it does not boot on the USB anymore but that’s because EUFI was not the first boot item anymore. It is fixed when I reset it properly.
So my feeling is that I created a bootable key and not an installation media.
Side note, I was using Home Assistant from CasaOS as a docker container but I’d like to have the full HAOS running on it.
That was my guess but then… how?
I though the documentation would create a bootable medium that I could use to do exactly that, a bit like when you create a USB key to flash a Windows machine.
Create a bootable linux live usb-stick
start with it
download USBImager and the latest HA OS on it
install usbimager
flash the downloaded HA OS to your internal ZimaBoard drive
Create a “live operating system” on a USB device running e.g. Ubuntu (how-to guide). Insert it into your system and boot the live operating system. Then follow from step 2 in “Write the image to your boot medium”.