I’m trying to run Ubuntu Core 20 on Raspberry Pi Zero 2 W.
According to Install Ubuntu on RPi this should work without a problem when using the 32bit version. Or with 64bit version using following procedure Ubuntu Server support for Zero 2 W.
I tried both options but my RPi Zero 2 W refuses to bootup -> according to LED code 7x blinks this means it’s unable to find kernel.img.
Can I ask if someone has some idea or procedure on how to fix this?
Boot SD Card structure:
Folder PATH listing for volume ubuntu-seed
Volume serial number is 3227-A7E8
F:.
├───uboot
│ └───ubuntu
├───snaps
├───overlays
├───.disk
└───systems
└───20210630
├───assertions
├───snaps
└───kernel
└───dtbs
├───broadcom
└───overlays
PS F:\> ls
Directory: F:\
Mode LastWriteTime Length Name
---- ------------- ------ ----
d----- 6/30/2021 12:18 PM uboot
d----- 6/30/2021 12:18 PM snaps
d----- 6/30/2021 12:18 PM overlays
d----- 6/30/2021 12:18 PM .disk
d----- 6/30/2021 12:18 PM systems
-a---- 6/30/2021 12:18 PM 791356 start4cd.elf
-a---- 6/30/2021 12:18 PM 3176 fixup4cd.dat
-a---- 6/30/2021 12:18 PM 47761 bcm2711-rpi-400.dtb
-a---- 6/30/2021 12:18 PM 19840 bcm2837-rpi-cm3-io3.dtb
-a---- 6/30/2021 12:18 PM 733 config.txt
-a---- 6/30/2021 12:18 PM 5429 fixup4.dat
-a---- 6/30/2021 12:18 PM 3176 fixup_cd.dat
-a---- 6/30/2021 12:18 PM 20933 bcm2837-rpi-3-b-plus.dtb
-a---- 6/30/2021 12:18 PM 20513 bcm2837-rpi-3-b.dtb
-a---- 6/30/2021 12:18 PM 556936 uboot_rpi_arm64.bin
-a---- 6/30/2021 12:18 PM 8436 fixup4x.dat
-a---- 6/30/2021 12:18 PM 8440 fixup4db.dat
-a---- 6/30/2021 12:18 PM 47733 bcm2711-rpi-cm4.dtb
-a---- 6/30/2021 12:18 PM 4638 boot.scr
-a---- 6/30/2021 12:18 PM 7301 fixup.dat
-a---- 6/30/2021 12:18 PM 47600 bcm2711-rpi-4-b.dtb
-a---- 6/30/2021 12:18 PM 2940128 start.elf
-a---- 6/30/2021 12:18 PM 791356 start_cd.elf
-a---- 6/30/2021 12:18 PM 71191 psplash.img
-a---- 6/30/2021 12:18 PM 514944 uboot_rpi_3.bin
-a---- 6/30/2021 12:18 PM 4788712 start_db.elf
-a---- 6/30/2021 12:18 PM 26277 bcm2710-rpi-cm3.dtb
-a---- 6/30/2021 12:18 PM 3716808 start4db.elf
-a---- 6/30/2021 12:18 PM 117 cmdline.txt
-a---- 6/30/2021 12:18 PM 10288 fixup_db.dat
-a---- 6/30/2021 12:18 PM 28587 bcm2710-rpi-3-b-plus.dtb
-a---- 6/30/2021 12:18 PM 20064 bcm2837-rpi-3-a-plus.dtb
-a---- 6/30/2021 12:18 PM 3698952 start_x.elf
-a---- 6/30/2021 12:18 PM 10288 fixup_x.dat
-a---- 6/30/2021 12:18 PM 2975368 start4x.elf
-a---- 6/30/2021 12:18 PM 52456 bootcode.bin
-a---- 6/30/2021 12:18 PM 27968 bcm2710-rpi-3-b.dtb
-a---- 6/30/2021 12:18 PM 26470 bcm2710-rpi-2-b.dtb
-a---- 6/30/2021 12:18 PM 570336 uboot_rpi_4.bin
-a---- 6/30/2021 12:18 PM 2215776 start4.elf
-a---- 1/1/2022 7:45 PM 27137 bcm2710-rpi-zero-2.dtb
Folder PATH listing for volume ubuntu-boot
Volume serial number is 25E6-AC61
E:.
├───uboot
│ └───ubuntu
│ ├───pi-kernel_302.snap
│ │ └───dtbs
│ │ ├───broadcom
│ │ └───overlays
│ ├───pi-kernel_376.snap
│ │ └───dtbs
│ │ ├───broadcom
│ │ └───overlays
│ └───pi-kernel_377.snap
│ └───dtbs
│ ├───broadcom
│ └───overlays
└───device
>Solution :
I do not think there is anything wrong with the image. The Ubuntu Core 20 image was made before RPi Zero 2. You can try modifying the boot after install to make it more like Ubuntu Server 21.10, but I think the reference mention of Zero 2 on the website for Core 20 was a mistake.
For example, I followed the guidance at the end of this post, "https://qengineering.eu/install-64-os-on-raspberry-pi-zero-2.html", and I was able to boot 64bit Ubuntu Server 21.10 on my Pi Zero 2.