Installing k3s on Ubuntu on Raspberry Pi
Having reinstalled all of my nodes with Ubuntu, I need to go back and install k3s. Joy.
Install needed modules
Per k3s#4234, k3s requires some extra modules that aren’t installed by default on Ubuntu.
sudo apt install linux-modules-extra-raspi
Install k3s control plane
Following the instructions at https://rancher.com/docs/k3s/latest/en/quick-start/
On the first node:
curl -sfL https://get.k3s.io | sh -
Then wait, occasionally running sudo k3s kubectl get nodes to check on progress.
Install k3s agents
Once that’s completed, grab the server token:
sudo cat /var/lib/rancher/k3s/server/node-token
Then on the other nodes:
curl -sfL https://get.k3s.io | K3S_URL=https://rpi401:6443 K3S_TOKEN=<node-token> sh -
KUBECONFIG
Back on the primary node:
mkdir ~/.k3s
sudo cp /etc/rancher/k3s/k3s.yaml ~/.k3s/k3s.yaml
sudo chown $USER.$USER ~/.k3s/k3s.yaml
export KUBECONFIG=$HOME/.k3s/k3s.yaml # add this to ~/.bashrc
Shell auto-completion
Per https://kubernetes.io/docs/tasks/tools/included/optional-kubectl-configs-bash-linux/
echo 'source <(kubectl completion bash)' >>~/.bashrc
Is it working?
$ kubectl get nodes
NAME STATUS ROLES AGE VERSION
rpi401 Ready control-plane,master 80m v1.21.7+k3s1
rpi405 Ready <none> 28s v1.21.7+k3s1
rpi404 Ready <none> 18s v1.21.7+k3s1
rpi403 Ready <none> 18s v1.21.7+k3s1
rpi402 Ready <none> 32s v1.21.7+k3s1