Docker - Build rpi image on Mac

Question

This could be more generic and be building an image for architecture B with a machine architecture A. I currently want to create an image with lot of Python dependencies. Which take time on raspberry-pi but is faster on Mac. When I get an error at the end well need to rebuild. Is there a way to build this image on Mac and then pull it on my raspberry pi ?

Answer 1

Emulating a full alternate architecture is generally very slow. QEMU is what allows you to do this on Linux and can be integrated into a Docker container.

For building, you can use QEMU User Emulation which is much quicker than full emulation. This allows your hardware to execute ARM binaries directly and is used to ease cross-compilation and cross-debugging.

First get VirtualBox and get Vagrant and install. (Or use docker-machine from the Docker Toolbox)

Setup your VM

mkdir raspbian-docker
cd raspbian-docker
vagrant init debian/jessie64
vagrant up
vagrant ssh

Now you are on your Debian Linux VM, setup the Docker host

sudo su -
apt-get install qemu-user-static
curl https://get.docker.com/ | sh

Run a raspbian environment

docker run -ti \
  --volume /usr/bin/qemu-arm-static:/usr/bin/qemu-arm-static \
  philipz/rpi-raspbian \
  bash

And do what you need to.

Then you can docker export and docker import to move images around. You can also use the hub or setup a registry to use push/pull

The Docker Toolbox will also allow you to easily run Docker via a VirtualBox VM on mac but I've run into more troubles than it's been worth (when you have vagrant setup).