Boot from MMC on OrangePi5b with SD Card Inserted

[sjohn]

I have been looking around for a way to boot OrangePi5b from the eMMC drive while a blank for formatted SD Card is inserted for extra storage space.

 

I dd wrote the debian server image to flash, booted and got no display, connected by ssh and it does recognized the eMMC storage. Download Armbian-legacy-bookworm image and dd'd that to the EMMC and it boots with a working display. Great, did a lot of work setting up Xorg with task-xfce4-desktop, xfce4-goodies, pulseaudio, firefox-esr, brave. gtkterm, tigervnc-viewer, remmina, wine32 for winbox, winbox and all working but was not able to find a way to boot with the SD card inserted. After checking many hints online, all did not work including dd'ing over some parts of the SD card and changing the UUID trying various options in armbian-install and armbian-config. I finally came up with a partial (not clean) solution which was to leave the boot partition on the SD card and have it boot to the MMC drive by changing the UUID target in the SD /boot partition and making the rest of the card an ext4 linux partition for storage/removable storage.

 

I installed Armbian to the flash, using either the legacy default image or one I made from the eMMC drive, so this boots to the SD card. Boot without the flash to the eMMC drive, put in the flash, mount p2 to /mnt and p1 to /mnt/boot. Then cp /boot/armbianEnv.txt /mnt/boot which copies the eMMC startup UUID to the flash boot. umount /mnt/boot and /boot used gparted to delete p2 and reformat as linux ext4. Then modify /etc/fstab on the EMMC card as... .. you could also use the UUID off the SD card but for flexibility of using different cards I also tried it by partition number.

 

My extra storage is called /raid5 because I have a couple Dell servers running FreeBSD and Debian that I use for running VM's and as desktops so it's just easy to remember my extra storage is called /raid5 on all platforms but it could be named anything. Use the noauto examples to disable automatic mount at boot.

 

#UUID=42818470-0ff3-41a1-84c0-85aac28901dc      /raid5  ext4    defaults,noauto 0      2
# next line works for parition2 on any SD card, if boot setup properly
/dev/mmcblk1p2  /raid5          ext4    defaults        0       2 
#/dev/mmcblk1p2 /raid5          ext4    defaults,noauto 0       2 
 

Disk free shows up like this... a little non-standard since /boot is mounted from the SD Card not the EMMC, but take the card out it boots from the EMMC perfectly, so it works well enough though doesn't seem to be a clean solution.

 

root@orangepi5:/boot# df
Filesystem     1K-blocks    Used Available Use% Mounted on
udev             3923712       0   3923712   0% /dev
tmpfs             813080   11300    801780   2% /run
/dev/mmcblk0p2  59222844 7776916  50808200  14% /
tmpfs            4065392       0   4065392   0% /dev/shm
tmpfs               5120       0      5120   0% /run/lock
tmpfs            4065392       8   4065384   1% /tmp
/dev/mmcblk1p1    261864  106300    155564  41% /boot
/dev/mmcblk1p2 122001932      24 115758376   1% /raid5
/dev/zram1         47960   11272     33104  26% /var/log
tmpfs             813076      16    813060   1% /run/user/0
 

 

Please if anyone has a better solution to boot from the EMMC on OrangePi5b with a blank SD Card inserted let me know!

 

sjohn

[sjohn]

Correction umount /mnt/boot and umount /mnt...