Kubear

Kubear is an Ansible playbook that creates a ready-to-use Kubernetes bare metal cluster that's meant to be running on Raspberry Pis. It aims to provide the cluster with as little preparatory work as possible. Once rolled out, you'll have a fully functional cluster with the following components:

• Container runtime: containerd
• CNI: Cilium
• Sealed-Secrets

Preliminaries

The nodes must be initially accessible via the ansible ssh configuration in the inventory group vars. If you add a new user via the users role you
can change the ansible config after the first successful run. Also make sure the correct ssh port is still configured as this might have changed by the security role while configuring ssh. To avoid to accidentally lock yourself out, it's probably best to have a shell open on your nodes while performing changes to the ssh config.

Getting Started

Download the imported roles:

ansible-galaxy install -r requirements.yml

Specify all the hosts that should form the cluster in your inventory hosts file. There are three groups available:

• [k8s_master]: Should only contain a single entry for the master node (runs kubeadm init)
• [k8s_cp]: Nodes that should join the cluster as additional control-plane nodes
• [k8s_worker]: Nodes that should join the cluster as worker nodes

If you want to initialize a new cluster, make sure to set k8s_join_only: false. Set k8s_join_only: true if a cluster is already running, and you want to join a new node.

If you want to reset and recreate the cluster from scratch set k8s_reset_cluster: true.

Tested Hardware

Raspberry Pi 4 Model B - 8GB

OS: Ubuntu Server 20.04

Arch: ARM64