I have a 8gb SD card and 64gb eMMC.  I want to put Armbian on the SD and use eMMC for high disk usage activities.

 

When using the eMMC it will always boot of that device.

 

You can alter the boot.ini to get it to boot off the SD once it reads the boot information from the eMMC.

 

I installed Odroid Mate on BOTH the eMMC (to get the boot partition created) and the SD I can get it to use the installed OS from the SD card.

Original Odroid boot.ini from eMMC:

setenv bootargs "root=UUID=74ce0af9-be77-4ebe-9308-c06feb2ecef9 rootwait ro ${condev} no_console_suspend ...
# Booting
fatload mmc 0:1 ${initrd_loadaddr} uInitrd
fatload mmc 0:1 ${loadaddr} Image
fatload mmc 0:1 ${dtb_loadaddr} meson64_odroidc2.dtb

I am changing bits and pieces together I have found online.

setenv bootargs "root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro ${condev} no_console_suspend ...
# Booting
fatload mmc 1:1 ${initrd_loadaddr} uInitrd
fatload mmc 1:1 ${loadaddr} Image
fatload mmc 1:1 ${dtb_loadaddr} meson64_odroidc2.dtb

With only four changes – it works to boot Odroid’s image from the SD card.

 

The problem comes when I want to boot Armbian rather than Odroid’s image.

 

I changed the boot.ini like this:

setenv bootargs "root=UUID=e139ce78-9841-40fe-8823-96a304a09859 rootwait ro ${condev} no_console_suspend ...
# Booting
fatload mmc 1:1 ${initrd_loadaddr} uInitrd
fatload mmc 1:1 ${loadaddr} zImage
fatload mmc 1:1 ${dtb_loadaddr}  dtb/meson64_odroidc2.dtb

Essentially keeping the original changes I  made, plus the other differences I could see from Armbian’s boot.ini, which add a couple more changes.

 

With this boot.ini and Armbian installed on the SD, the Odroid C2 will start blinking the blue heartbeat light but nothing on the screen and not responsive to any ping or SSH attempt.  So I have no idea what it is doing (if anything).

 

Has anyone ever succeeded in doing this?

 

Since I can get it working with Odroid’s image there is hope, but I really want to run Armbian as I think there is more development being done on this build.

Try enabling boot console to screen (console=tty1) and enable verbosity (loglevel=9) and see where it stops.

 

I would guess that you need to alter /etc/fstab on your eMMC to change from:

 

/dev/emmcblk0p2 / ...

to

UUID=e139ce78-9841-40fe-8823-96a304a09859 / ...

Somewhere on ODROID's forums I've read that C2 always try to boot eMMC first, and there is no way to change that behavior.

 

So I suppose you could try to:

1. Flash Armbian on both your eMMC and SD card
2. Install both on your C2
3. Then fidget with the eMMC "/boot/boot.ini" so you use the SD card as root device
4. If you succeed, maybe you could consider delete everything on the eMMC except for the /boot dir, so you can reclaim its capacity back? I did something like that with Armbian, some OrangePi/BananaPi, some SDcards and a couple of USB flash drives/SATA hard drives.