Introduction

This project meta-azure-device-update serves as an example of embedding device update agent in a custom Linux-based system.

Disclaimer: There is no guarantee or support for this project. Please modify and customize the project to fit your need, and reference this example as needed.

Prerequisite

The following instructions are based on Yocto Project, please find the basics of Yocto Project in https://www.yoctoproject.org/. The following instruction will guide you to create a Raspberry Pi Poky Yocto image with device update agent embedded.

Yocto Layers, Recipes, and Configuration

There are three main areas that will be covered:

• Yocto build configurations
• Meta-azure-device-update recipe
• Image install with A/B partitions

Yocto build configurations

This section describes the most important files of the Yocto build, including 'bblayers.conf.sample' and 'local.conf.sample' as well as the Yocto layers that need to be used.

Layer Name	Description
meta-azure-device-update	Provides the configuration and contains the recipes for installing both the ADU Agent and its dependencies as well as integrating them into the Yocto build layers.

bblayers.conf.sample

Usually this file would be located under yocto/config-templates/raspberrypi3.
The 'bblayers.conf.sample' shows the complete list of Yocto layers included in the build.

POKY_BBLAYERS_CONF_VERSION = "3"

BBPATH = "${TOPDIR}"
BBFILES ?= ""

BBLAYERS ?= " \
  ##OEROOT##/meta \
  ##OEROOT##/meta-poky \
  ##OEROOT##/meta-yocto-bsp \
  ##OEROOT##/../meta-openembedded/meta-oe \
  ##OEROOT##/../meta-openembedded/meta-multimedia \
  ##OEROOT##/../meta-openembedded/meta-networking \
  ##OEROOT##/../meta-openembedded/meta-python \
  ##OEROOT##/../meta-azure-device-update \
  "