https://github.com/brainphreak/k8s-raspberry-pi-cluster
This project documents the process of building a 6-node Kubernetes cluster using various models of Raspberry Pi
https://github.com/brainphreak/k8s-raspberry-pi-cluster
cluster kubernetes pi raspberry sbc
Last synced: 7 months ago
JSON representation
This project documents the process of building a 6-node Kubernetes cluster using various models of Raspberry Pi
- Host: GitHub
- URL: https://github.com/brainphreak/k8s-raspberry-pi-cluster
- Owner: brainphreak
- Created: 2025-11-08T09:17:59.000Z (7 months ago)
- Default Branch: main
- Last Pushed: 2025-11-08T09:32:35.000Z (7 months ago)
- Last Synced: 2025-11-08T11:24:21.185Z (7 months ago)
- Topics: cluster, kubernetes, pi, raspberry, sbc
- Homepage: https://www.brainphreak.net
- Size: 390 KB
- Stars: 0
- Watchers: 0
- Forks: 0
- Open Issues: 0
-
Metadata Files:
- Readme: README.md
Awesome Lists containing this project
README
# Raspberry Pi Kubernetes (K8s) Cluster
## Project Overview
This project documents the process of building a 6-node Kubernetes cluster using various models of Raspberry Pi. The goal was to create a functional, scalable, and redundant environment for deploying containerized applications and services, all while utilizing existing hardware. This serves as a practical exploration into container orchestration, network configuration, and system administration in a distributed environment.
## Key Features
* **6-Node Cluster:** Provides high availability and load balancing for deployed services.
* **Mixed Raspberry Pi Models:** Demonstrates compatibility across different Raspberry Pi versions (2B, 2B+, 3B, 3B+).
* **Centralized Power:** Utilizes a single multi-port USB hub to power all nodes, simplifying the physical setup.
## Technical Specifications
### Hardware
* (6) Raspberry Pi SBCs (Models: 2B, 2B+, 3B, 3B+)
* (1) 6-Node "Bramble" Case by C4Labs
* (1) Kamera 10-Port 120W USB Charging Hub
* (6) Micro USB Cables
* (6) Ethernet Cables
* (6) SD Cards (with Raspberry Pi OS installed)
### Software & Networking
* **Operating System:** Raspberry Pi OS
* **Container Orchestration:** MicroK8s
* **Networking:** Static IP addresses and a custom /etc/hosts file for hostname resolution.
## Cluster Setup and Configuration
### Step 1: Hardware Assembly and OS Preparation
The Raspberry Pis were assembled into the 6-node Bramble case. Each Pi was equipped with an SD card flashed with a fresh installation of Raspberry Pi OS.
### Step 2: Network Configuration
Before booting the cluster, each node was configured with a static IP address. A custom `/etc/hosts` file was created and distributed to all nodes to enable simple and reliable communication between them using hostnames (e.g., `pi-1`, `pi-2`).
```
# Example /etc/hosts configuration:
127.0.0.1 localhost localhost.local
10.0.0.21 pi-1 pi-1.local
10.0.0.22 pi-2 pi-2.local
10.0.0.23 pi-3 pi-3.local
10.0.0.24 pi-4 pi-4.local
10.0.0.25 pi-5 pi-5.local
10.0.0.26 pi-6 pi-6.local
```
### Step 3: Enable C-Groups
To ensure the Kubelet functions correctly, c-groups were enabled on each Raspberry Pi by modifying the `/boot/firmware/cmdline.txt` file and adding the following boot options:
```
cgroup_enable=memory cgroup_memory=1
```
After modifying the file, each node was rebooted.
### Step 4: Install MicroK8s
MicroK8s was installed on all 6 nodes using the command:
```bash
sudo snap install microk8s --classic
```
### Step 5: Cluster Formation
One node (`pi-1`) was designated as the master node. The following command was run on the master to generate a join token for the other nodes:
```bash
sudo microk8s.add-node
```
### Step 6: Join Worker Nodes
On each of the remaining 5 nodes, the `microk8s.join` command provided by the master was executed to join them to the cluster.
### Step 7: Verify Cluster Status
After a few minutes, the cluster status was verified from the master node using `kubectl`. The output confirmed that all 6 nodes were in a `Ready` state.
```bash
microk8s.kubectl get node
```
**Output:**
```
NAME STATUS ROLES AGE VERSION
pi-1 Ready master 1h v1.14.6+888f9c630
pi-2 Ready 1h v1.14.6+888f9c630
pi-3 Ready 1h v1.14.6+888f9c630
pi-4 Ready 1h v1.14.6+888f9c630
pi-5 Ready 1h v1.14.6+888f9c630
pi-6 Ready 1h v1.14.6+888f9c630
```
## Conclusion
This project successfully demonstrates the creation of a fully functional Kubernetes cluster on low-power Raspberry Pi hardware. It serves as a testament to the versatility of single-board computers and the power of container orchestration. The cluster is now ready for deploying and managing containerized applications in a high-availability environment.