Migrating to Yocto - A Guide and Lessons Learned

Explore a comprehensive guide on migrating to Yocto, based on the experiences of Muhammad Tauqir Ahmad and Ram from Cisco Meraki. Learn about the motivations behind their decision to transition the entire engineering organization's build system, including the need to support a new platform and modernize their outdated OpenWRT-based system. Discover the technical challenges faced during the migration process, such as integrating proprietary software with Yocto, ensuring build correctness, and adapting to various use cases within Meraki. Gain insights into the human aspects of large-scale migrations, including stakeholder buy-in, documentation, and maintenance processes. Follow the step-by-step approach to porting packages from OpenWRT to Yocto, utilizing appends, layers, and matching versions. Understand the importance of organizing porting days, providing tutorials, and using task management tools for successful implementation. Explore Yocto extensions developed for specific needs, such as building from disk and creating custom machine and distro features. Examine solutions to common problems like mismatched C library headers and non-programmatically selectable layers. Evaluate the successes achieved, including improved build times, widespread adoption across products, and easier maintenance. Benefit from the lessons learned and closing thoughts shared by the presenters to guide your own Yocto migration journey.

Intro
Repository Layout
Legacy Build System
Unmaintainable OpenWRT
Legacy Builds are Painful
Summary
Follow the Quick Start Guide
Build Your Own Image
Porting from OpenWRT
Refresher: Appends
Refresher Layers
Back to Porting Packages
Add an Append
Match Versions
Apply the Same Patches
Use the Same Configure Options
Yocto Porting Day
Porting Day - 1 week
Give a Tutorial
Use Task Management Tools
Great Success!
Tip: Recruit People
Extend Yocto for Your Needs
Building from Disk: EXTERNALSRC
Building from Disk: SRC_URI
We Built Merakisc
Machine & Distro Features
We Built Meraki Features
Problem: Mismatched C Library Headers
The Error
The User-space App
Solution: Use the Same Sources
Layers Are Not Programmatically Selectable
Successes: Build Times
Successes: Most Products Using Yocto
Successes: Easy Maintenance
Closing Thoughts