We can setup Mender Client on a Dual Gigabit Ethernet Carrier Board for Raspberry Pi Compute Module 4 and then receive OTA updates from a Hosted or Self-Hosted Mender Server.
This guide focuses on using a Dual Gigabit Ethernet Carrier Board for RPi CM4 running a custom Linux System compiled using the Yocto Project.
The Yocto Project releases in the table below have been tested by the Mender community. Please update it if you have tested this integration on other Yocto Project releases:
|dunfell (3.1 / 5.3.0)||test works||test works|
Build Means that the Yocto Project build using this Mender integration completes without errors and outputs images. Runtime Means that Mender has been verified to work on the board. For U-Boot-based boards, the integration checklist has been verified.
- A supported Linux distribution and dependencies installed on your workstation/laptop as described in the Yocto Mega Manual
- NOTE. Instructions depend on which Yocto version you intend to use.
- Dual Gigabit Ethernet Carrier Board for RPi CM4
Configuring the build
Setup Yocto environment
Create a directory for your
mender-dual-gbe-cm4 setup to live in and clone the meta information.
mkdir mender-dual-gbe-cm4 && cd mender-dual-gbe-cm4
Get all of necessary layers:
git clone -b master git://git.yoctoproject.org/poky layers/poky
git clone -b dunfell https://github.com/Seeed-Studio/meta-seeed-cm4.git layers/meta-seeed-cm4
git clone -b master git://git.yoctoproject.org/meta-raspberrypi layers/meta-raspberrypi
git clone -b dunfell https://github.com/openembedded/meta-openembedded.git layers/meta-openembedded
git clone -b dunfell git://github.com/mendersoftware/meta-mender layers/meta-mender
In order to be compatible with meta-raspberrypi, change the gstreamer version of poky to the latest
cp -r meta/recipes-multimedia/gstreamer/ ../
git checkout dunfell
rm -r meta/recipes-multimedia/gstreamer/
cp -r ../gstreamer/ meta/recipes-multimedia/
rm -r ../gstreamer/
Modify the meta-raspberrypi to avoid compile error
sed -i '/^LAYERSERIES_COMPAT_raspberrypi/s/= .*$/= "honister dunfell"/g' conf/layer.conf
sed -i 's/arm\/armv8a\///g' conf/machine/raspberrypi4-64.conf
Modify the meta-mender to avoid compile error
sed -i 's/"0x4000"/"0x1f000"/g' meta-mender-raspberrypi/recipes-bsp/u-boot/u-boot-raspberrypi.inc
sed -i 's/bootfiles/rpi-bootfiles/g' meta-mender-core/classes/mender-part-images.bbclass
Setup build environment
Initialize the build environment:
Add yocto project layers:
bitbake-layers add-layer ../layers/meta-raspberrypi
bitbake-layers add-layer ../layers/meta-seeed-cm4
bitbake-layers add-layer ../layers/meta-openembedded/meta-oe
bitbake-layers add-layer ../layers/meta-openembedded/meta-python
bitbake-layers add-layer ../layers/meta-mender/meta-mender-core
bitbake-layers add-layer ../layers/meta-mender/meta-mender-raspberrypi
bitbake-layers add-layer ../layers/meta-mender/meta-mender-demo
Configure Mender server URL (optional)
This section is not required for a successful build but images that are generated by default are only suitable for usage with the Mender client in Standalone deployments, due to lack of server configuration.
You can edit the
conf/local.conf file to provide your Mender server configuration, ensuring the generated images and Mender Artifacts are connecting to the Mender server that you are using. There should already be a commented section in the generated
conf/local.conf file and you can simply uncomment the relevant configuration options and assign appropriate values to them.
Build for Hosted Mender:
# To get your tenant token:
# - log in to https://hosted.mender.io
# - click your email at the top right and then "My organization"
# - press the "COPY TO CLIPBOARD"
# - assign content of clipboard to MENDER_TENANT_TOKEN
MENDER_SERVER_URL = "https://hosted.mender.io"
MENDER_TENANT_TOKEN = "<copy token here>"
Build for Mender Demo Server:
MENDER_DEMO_HOST_IP_ADDRESS = "<IP address of Mender demo server>"
Build for Mender Production/ Self-Hosted (on-prem):
# Uncomment below and update the URL to match your configured domain
# name and provide the path to the generated server.crt file.
# Note that a custom server.crt file is only necessary if you are using
# self-signed certificates.
# NOTE! It is recommend that you provide below information in your custom
# Yocto layer and this is only for demo purposes. See linked documentation
# for additional information.
MENDER_SERVER_URL = "<URL of Self-Hosted Mender Server>"
FILESEXTRAPATHS_prepend_pn-mender-client := "<DIRECTORY-CONTAINING-server.crt>:"
SRC_URI_append_pn-mender-client = " file://server.crt"
Building the image
You can now proceed with building an image:
MACHINE="dual-gbe-cm4-mender" bitbake core-image-base
core-image-base with your desired image target.
Using the build output
After a successful build, the images and build artifacts are:
if you already have Mender running on your device and want to deploy a rootfs update using this build, you should use the Mender Artifact files, which have
.mender suffix. You can either deploy this Artifact in managed mode with the Mender server (upload it under Releases in the server UI) or by using the Mender client only in Standalone deployments.
Please follow this wiki guide to learn about flashing the above image to the eMMC on the board.
Once flashed, when you turn on the reTerminal, it will boot from the compiled image.
If you see the following log from UART, that means the system has successfully booted
[ OK ] Started Kernel Logging Service.
[ OK ] Started System Logging Service.
[ OK ] Started D-Bus System Message Bus.
[ OK ] Started Getty on tty1.
Starting Telephony service...
[ OK ] Started Serial Getty on ttyS0.
[ OK ] Reached target Login Prompts.
[ 7.340436] audit: type=1334 audit(1638186061.687:4): prog-id=7 op=LOAD
[ 7.347278] audit: type=1334 audit(1638186061.691:5): prog-id=8 op=LOAD
Starting Login Service...
[ OK ] Started Save/Restore Sound Card State.
[ 7.386306] Bluetooth: Core ver 2.22
[ 7.390103] NET: Registered protocol family 31
[ 7.394856] Bluetooth: HCI device and connection manager initialized
[[ 7.401967] Bluetooth: HCI socket layer initialized
OK 7.407591] Bluetooth: L2CAP socket layer initialized
0m] Reac[ 7.413409] Bluetooth: SCO socket layer initialized
hed target Sound Card.
[ OK ] Started Telephony service.
[ OK ] Started Avahi mDNS/DNS-SD Stack.
[ OK ] Started Login Service.
Poky (Yocto Project Reference Distro) 3.1.12 dual-gbe-cm4-mender ttyS0
dual-gbe-cm4-mender login: root
[Web Page] Mender Official Documentation
[Web Page] Yocto Official Documentation
[Web Page] Raspberry Pi CM4 Official Documentation
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