How to push a multi-architecture Docker image to Docker Hub - x86_64

For the last 6 months I read a lot about multi-architecture docker images. I first read this one from IBM and was still a little puzzled. I then read this one by @stefscherer which was easier to read and gave some ideas. I finally read this last one and decided to try it myself.

My Goal

I use a lot of images for my home automation and some website I host at home. All those images are hosted on 2 Banana Pis so Arm32V7. Those images are now build on one of my Banana Pi from this repository. I’ve made one big repository because most of my images are fully based on alpine, I only use apk to install others packages.

I also have a Pine64 lying around so Arm64v8. It will maybe replace / complement my Banana Pi someday.

My goal is to provide images from ARM32v7, ARM64v8 and x86_64.

Baby steps - x86_64 first

Basic images

I have no server available to build any x86_64 images (beside my work laptop, I’m all ARM at home). I first thought to use a VPS / Public cloud resource and ended trying to use automatic builds provided by docker hub.

The configuration was easy for simple images, I ended up using it with tags only :

In my case the Dockerfile Location is inside a directory. I also take care to use a prefix for the tag of my image.

You just have to push a tag to Github and the new image should be pushed to the Hub automatically. It might take some time though !

x86_64 - dependencies

In my case the image alpine-python3-cron is using alpine-python3 as its base image. So I have to ensure that they are build in order. It seems to be handled with Repository Links, see the image below.

I also added another tag to make sure the dependency can be found.

Conclusion

Now each time I push a new tag to my docker-images repository, new images are created on Docker Hub with this tag : amd64-{NAME OF THE GITHUB TAG}.

Every image is created within the hour which is not that bad.

Next steps

Two more architectures and the manfiest to go !