What do you do when you like tinkering with Docker and have an old Raspberry Pi lying around?
You bring the two together and make a Docker host out of the RPi with docker-machine, docker-compose and all that nice stuff.
I love the idea of docker-compose: being able to encapsulate applications and simple commands in a Docker image without worrying about the underlying host.
Enter Hypriot.
A bunch of clever people already decided to run Docker on an RPi— you can find them here. They provide ready-made images for the RPi.
It was my first time playing with a machine like that and it took me around 20 minutes to get it running.
I followed their “Getting started guide”, with only one difference: I used their latest image as described in this article.
Without much explanation, here are the commands I used. Not much different from their guide:
diskutil list
diskutil unmountdisk /dev/disk2
sudo dd if=hypriot-rpi-20151115-132854.img of=/dev/rdisk2 bs=1m
diskutil unmountdisk /dev/disk2
After that I inserted the card into the RPi, attached a screen and keyboard, and started it up by plugging in the power cord. I logged in once to find the IP address and then connected with SSH from my Mac to start the container. Then I removed the screen and keyboard again. I like a clean desk— I’m known for it.
ssh root@192.168.178.10
docker run -d -p 80:80 hypriot/rpi-busybox-httpd
Uuups— I ran into a little problem here:
HypriotOS: root@black-pearl in ~ $ docker run -d -p 80:80 hypriot/rpi-busybox-httpd
Unable to find image 'hypriot/rpi-busybox-httpd:latest' locally
Pulling repository docker.io/hypriot/rpi-busybox-httpd
Error while pulling image: Get https://index.docker.io/v1/repositories/hypriot/rpi-busybox-httpd/images: x509: certificate has expired or is not yet valid
I found the answer by searching the hypriot channel on Gitter.
I fixed the issue with:
date -s "19 NOV 2015 23:24:00"
and started the container again:
docker run -d -p 80:80 hypriot/rpi-busybox-httpd
On my Mac I pointed my browser to 192.168.178.10 and saw a nice welcome screen:
Cool— I have the hammer, now I just need a nail…
Done for today!