This document discusses building multi-architecture Docker images using Docker Buildx. It introduces the concepts of multi-architecture images, describes the traditional method of building separate images for each architecture and combining them with manifest lists, and recommends using Buildx which can build images for multiple architectures simultaneously during a single build. Buildx allows building on the host architecture natively or emulating other architectures. The document emphasizes that applications should support multiple platforms and architectures, and encourages always using multi-stage Dockerfiles and considering Buildx as an improved alternative to the older manifest-based approach.

1. Docker + Arm
Building multi-arch apps with `buildx`
@EltonStoneman | elton@docker.com

2. • Understanding multi-arch images
• Multi-arch the old way
• Multi-arch with `buildx`

3. > docker container run...

4. > docker container run...

5. > docker container run...

6. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker container run...

7. > docker container run...
os linux
architecture arm

8. > docker container run...
os linux
architecture arm
os linux
architecture amd64
os windows
architecture amd64
os linux
architecture arm64

9. > docker container run...
os linux
architecture arm
os linux
architecture amd64
os windows
architecture amd64
os linux
architecture arm64
my-app
os *
architecture *

10. my-app
os *
architecture *
> docker container run...
os linux
architecture arm
os linux
architecture amd64
os windows
architecture amd64
os linux
architecture arm64
Build-time diversity
Run-time diversity
Cloud Arm instances
Edge & IoT

11. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker container run...

12. > demo

13. Multi-arch: the old way

14. OS
CPU
OS
CPU
OS
CPU
OS
CPU

15. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker image build...

16. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker image build...

17. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker image push...

18. > docker manifest create...
my-app:linux-arm
os linux
architecture arm
my-app:linux-amd64
os linux
architecture amd64
my-app:windows-amd64
os windows
architecture amd64
my-app:linux-arm64
os linux
architecture arm64

19. > docker manifest push...
my-app:linux-arm
os linux
architecture arm
my-app:linux-amd64
os linux
architecture amd64
my-app:windows-amd64
os windows
architecture amd64
my-app:linux-arm64
os linux
architecture arm64
my-app
os *
architecture *

20. > docker image pull myapp
my-app:linux-arm
os linux
architecture arm
my-app:linux-amd64
os linux
architecture amd64
my-app:windows-amd64
os windows
architecture amd64
my-app:linux-arm64
os linux
architecture arm64
my-app
os *
architecture *

21. > demo

22. Multi-arch: with `buildx`

23. OS
CPU
> docker buildx build...
Native

24. OS
CPU
> docker buildx build
--platform ...
Emulated

25. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker buildx create...

26. OS
CPU
OS
CPU
OS
CPU
OS
CPU
> docker buildx build
--platform ...
--push ...

27. > demo

28. TAKEAWAYS
• Everything should be multi-platform
• Always use multi-stage Dockerfiles
• `buildx` is experimental but solid (based on BuildKit)
• Alternatively use `docker manifest`… also experimental :)

29. NEXT STEPS
• Today’s demos | is.gd/2ad2c9
• DIAMOL – Manning 40% discount | webdoc40
• Docker learning path on Pluralsight | is.gd/O0fYmU
• DockerCon 2020 | Austin TX, June 15-18

30. THANK YOU :)
@EltonStoneman | elton@docker.com