A few months ago someone told me about a new Raspberry Pi Compute Module 4 cluster board, the DeskPi Super6c.
You may have heard of another Pi CM4 cluster board, the Turing Pi 2, but that board is not yet shipping. It had a very successful Kickstarter campaign, but production has been delayed due to parts shortages.
tl;dr: This website is currently being hosted off-grid, on a cluster of Raspberry Pis, via 4G LTE—or at some points through the same tunnel via WiFi if signal strength gets too low. Here's the GitHub repo for the project.
Note: The website was down for a few hours this morning, as shortly after this post I started getting a 40-50 Mbps flood of POST requests (over 6 million in a 30 minute time frame)... and yeah, no way the little Pi cluster could handle that. Thanks, Internet. It's back up through Cloudflare now, and I'll post more on this 'fun' experience later.
A couple weeks ago, after months of preparation, I took my 4-node Turing Pi 2 cluster (see my earlier review) to my cousin's farm, and ran this website (JeffGeerling.com) on it, live on the Internet—completely disconnected from grid power or hard-wired Internet.
Recently I needed to test the full HTTP stack between a Kubernetes cluster's member nodes and an external Internet routing setup, and so I wanted to quickly install K3s (which includes Traefik by default, and load balances through ports 80 and 443 on all nodes), then get a quick 'hello world' web page up, so I could see if the traffic was routing properly all the way from the external host through to a running container exposed via Traefik Ingress.
Here's how I set up a basic 'Hello World' web page on my K3s cluster:
First, I created an HTML file to be stored as a ConfigMap. Create a file named index.html with the following contents:
<html>
<head>
<title>Hello World!</title>
</head>
<body>Hello World!</body>
</html>
Create a ConfigMap with the HTML from the file you just created:
$ kubectl create configmap hello-world --from-file index.html
Save the following to Kubernetes resource definitions into a file named hello-world.yml:
A few months ago, in the 'before times', I noticed this post on Hacker News mentioning the Turing Pi, a 'Plug & Play Raspberry Pi Cluster' that sits on your desk.
It caught my attention because I've been running my own old-fashioned 'Raspberry Pi Dramble' cluster since 2015.
So today, I'm wrapping up my Raspberry Pi Cluster series with my thoughts about the Turing Pi that I used to build a 7-node Kubernetes cluster.
This blog post has a companion video embedded below:
This is the fourth video in a series discussing cluster computing with the Raspberry Pi, and I'm posting the video + transcript to my blog so you can follow along even if you don't enjoy sitting through a video :)
In the last episode, I showed you how to install Kubernetes on the Turing Pi cluster, running on seven Raspberry Pi Compute Modules.
In this episode, I'm going to show you some of the things you can do with the cluster.
This is the third video in a series discussing cluster computing with the Raspberry Pi, and I'm posting the video + transcript to my blog so you can follow along even if you don't enjoy sitting through a video :)