Swarming Raspberry Pi part 1. via matthewkwilliams
Here’s the first in a series of building a robust docker swarm of raspberry pi hosts. This installment goes through installing the Pi(s), modifiying the Docker Daemon config, and starting up a test to verify that everyone can join the cluster.
The cluster which I am using consists of
• Raspberry Pi B+ x 5
• Raspberry Pi 2 B x 5
In order to verify that the cluster is working properly, there should be ten (10) members, five (5) of which have 4 cores.
Obtaining the OS and Setup
The wonderful folks at Hypriot have produced a raspberry image based on Raspbian, but with Docker 1.5.0. The image and instructions can be found at Heavily ARMed after major upgrade: Raspberry Pi with Docker 1.5.0 – Docker Pirates ARMed with explosive stuff.
Note: The image resizes itself to fit the card upon the first boot and then reboots. This takes a little bit (minutes at most). Just don’t be surprised when it reboots.
In order for this to work properly, the hosts need a unique name. It’s sometimes possible to configure DHCP to do this, but I went ahead and edited /etc/hostname myself since I wanted the most portability possible.
Like all good sysadmins, I am lazy. Doing the same thing over and over is boring. Besides, that’s what computers are for. So I wrote a script to make copies of the image and then edit the hostnames. Once that’s done I can then proceed to write the images to the SD cards.
The following script takes one argument, the location of the image you wish to modify — this should work for more than just Hypriot; it should work for just about any Rasberry Pi image. At present, it creates 10 instances and the NAME starts with apis-rpi- — you will likely want to change those. I may make the file a bit more generic at some point.
Each Friday is PiDay here at Adafruit! Be sure to check out our posts, tutorials and new Raspberry Pi related products. Adafruit has the largest and best selection of Raspberry Pi accessories and all the code & tutorials to get you up and running in no time!
Have an amazing project to share? Join the SHOW-AND-TELL every Wednesday night at 7:30pm ET on Google+ Hangouts.
Join us every Wednesday night at 8pm ET for Ask an Engineer!
Learn resistor values with Mho’s Resistance or get the best electronics calculator for engineers “Circuit Playground” – Adafruit’s Apps!
Maker Business — Raspberry Pi and CoderDojo Join Forces
Wearables — Gold glow
Electronics — Linear Love
Biohacking — Nike’s Unlimited Stadium Will Put Your Best Foot Forward
No comments yet.
Sorry, the comment form is closed at this time.