Troubleshooting and FAQ
Troubleshooting tips and FAQ
Modifications from Standard Raspberry PI OS Lite
The SCM ships with a pre-installed version of either Raspberry PI OS Lite (bullseye 64bit) or Ubuntu Server 22.04 (jammy) with a more secure configuration.
The pre-installed image is encrypted and cannot be replaced via rpiboot
. Once Bootware is installed, Bootware can install new images based off Bullseye or Jammy in the Zymbit zi
image format. See the Getting Started section and the zb-update tool.
Important: The CM4/SCM firmware must include bootloader version 2023/01/11 or later in order to work with Ubuntu 22.04. The version can be verified with the vcgencmd bootloader_version
command. The firmware is not field upgradeable. If you have a CM4/SCM with an earlier version of the bootloader and need to run Ubuntu 22.04, please contact support@zymbit.com.
Precautions
HTTPS endpoints are limited to a zi image of approximately 6GB. The zi images are compressed, so this is not normally a limitation with A/B configurations. If you have zi imagest larger tha 6MB, download the image to a local device with 3x the image size space and use the local device endpoint.
Important boot files to not delete.
- Boot.scr
- zboot.enc
- u-boot.bin
- config.txt
- [After bootware update] usr-kernel.enc
- [Before bootware] cmdline.txt
- [Before bootware] kernel8.img for rpiOS and vmlinuz for ubuntu
The
/boot
filesystem should be partitioned for 512MB of space or more. Our default configuration as shipped uses a/boot
partition of 512MB. Ubuntu in particular creates backups of all files on updates that may exceed free space with Bootware.Turn off unattended-upgrades.
/boot/firmware/boot.scr
in ubuntu gets replaced by updates from apt and other services. This will brick the device if its booted on the ubuntu made boot.scr. Ubuntu does not use u-boot on the Pi but writes overboot.scr
. If ever doing a kernel update/upgrade, you mustcp boot.scr.bak boot.scr
prior to rebooting.In config.txt, otg_mode=1 can’t be set. DWC2 needs to be enabled. This is set at our factory and by bootware (and is the default with ubuntu), but if changed, the system will not boot.
Non Bootware: Ubuntu requires the initrd.img on their system to boot up. Be wary of replacing this file or removing it
Be cautious around the policies set in the supervised boot and the files put in the manifest. This follows hardware not images. This also applies to the other tamper policies.
Changes to our standard images
The table below summarizes changes made to the standard image.
Default | As Shipped |
---|---|
Boot partition of 256MB | 2x Boot partition size - 512MB |
Console login allowed | Disabled |
SSH optionally enabled | SSH with password allowed |
Hostname is raspberrypi | Hostname changed to zymbit-dev |
Default user of pi | Default user is zymbit . User pi removed. Passwd set to zymbit |