pi-cluster

**NOTE: Change your Pi hostnames! If they're all the default raspberrypi, k3s won't work correctly.

Prerequisites

1. Set up as many Raspbian SD cards as you need, with Raspbian Lite. Touch the /boot/ssh file so that SSH is enabled on first boot. (Possibly add SSH key to authorized_keys during this step?)
2. Add your ssh public key to every one of the hosts' authorized_keys file (not covered here) - you need to SSH into the Pi's individually and create this file.

On your machine (not the Raspberry Pis)

1. Install Ansible (not covered here)
2. sudo mkdir /etc/ansible && sudo pico /etc/ansible/hosts (add hosts in either yaml or INI style). For example, if you have 4 Pi's in the cluster:

[master]
k3s-master ansible_host=192.168.1.6
[workers]
k3s-worker-01 ansible_host=192.168.1.7
k3s-worker-02 ansible_host=192.168.1.8
k3s-worker-03 ansible_host=192.168.1.9

4. Assuming that you put your public SSH key in the pi user's .ssh/authorized_keys file, you'll want to run ansible as the pi user so it can login properly with the SSH key. Using --become tells Ansible to upgrade to sudo when necessary.

ansible-playbook ./playbooks/setup_cgroups.yml --user pi --become

The playbook will seem to fail because the Pi's should reboot at this point. Wait for them to come back, and run the next playbook...

ansible-playbook ./playbooks/setup_k3s.yml --user pi --become

6. If everything was set up correctly and this works, you can SSH into the master host and run kubectl get node -o wide to see all the nodes connected.