Create docker image on Apple Silicon M1 Mac

My biggest pain while moving to Apple Silicon M1 chip mac book was to create a docker build that would work on all the machines. It took some time for me to figure out how I can create docker images and share on docker hub that would work across different platforms.

By default Docker on M1 macbook would create linux/arm64 images, which would work only on the machines that are using ARM architecture. But intel based machines uses AMD architecture. As a result docker images built on m1 macbook might not work on intel based machines.

It might not even work on gcloud / aws k8s clusters 😄

But the good part is that m1 chip macbook supports linux/amd64 images, so we might only need to build docker images using linux/amd64.

Let me demonstrate an example here:

Consider you have a Golang Application and you need Docker image for that

So your Dockerfile might look like

FROM golang:1.16-alpine as builder
WORKDIR /app
COPY . .

RUN go build && \\
    chmod 777 docker-demo

FROM alpine:latest
WORKDIR /root/
COPY --from=builder /app/docker-demo .
CMD [ "./docker-demo" ]

Note this is just an example you can have any Dockerfile😄

Now the command to build should add --platform flag with the correct platform that you want to build docker image for.

Example

docker build --platform linux/amd64 -t lakhansamani/docker-demo .

Thats all 😅 Now you can publish your docker image on docker hub and share with people.

You can find demo code on this github repository