Get Hands-on with Cluster API - openSUSE 2023

This is a companion to the tutorial at openSUSE 2023.

Pre-reqs

To complete the tutorial yourself you will need to install the following:

• kind
• clusterctl
• Rancher Desktop or Docker Engine/Desktop
• kubectl
• (optional)k9s

Tutorial

If you have a Mac with Apple Silicon some of the sections will have alternative commands.

Create a management cluster

• Download kind-cluster-with-extramounts.yaml
• Run the following command in a terminal:

kind create cluster --config kind-cluster-with-extramounts.yaml

Configure clusterctl

For non Apple Silicon machines

• Download clusterctl.yaml
• Move it to the following directory: ~/.cluster-api/clusterctl.yaml

You will probably need to create the ~/.cluster-api directory.

For Apple Silicon machines

This step isn't required as we are using different providers.

Install Cluster API (and providers)

For non Apple Silicon machines

We need to install the Docker and RKE2 providers.

• In a terminal run the following:

clusterctl init -i docker2 -b rke2 -c rke2

For Apple Silicon machines

We need to install the Docker and Kubeadm providers.

• In a terminal run the following:

export EXP_CLUSTER_RESOURCE_SET=true
clusterctl init -i docker

Create workload/child cluster

For non Apple Silicon machines

• Open a terminal and run the following:

export CABPR_CP_REPLICAS=1
export CABPR_WK_REPLICAS=1
export KUBERNETES_VERSION=v1.26.4

clusterctl generate cluster test1 --from https://github.com/capi-samples/opensuse-23/blob/main/templates/online-default.yaml > cluster.yaml

For Apple Silicon machines

• Open a terminal and run the following:

export CONTROL_PLANE_MACHINE_COUNT=1
export WORKER_MACHINE_COUNT=1
export KUBERNETES_VERSION=v1.26.4

clusterctl generate cluster test1 --from https://github.com/capi-samples/opensuse-23/blob/main/templates/kubeadm-docker.yaml > cluster.yaml

Apply cluster definition

• Apply the cluster yaml to your management cluster

kubectl apply -f cluster.yaml

Observe cluster being provisioned

• Watch the Cluster being provisioned:

kubectl get clusters -A -w

• Watch the Machine being provisioned:

kubectl get machines -A -w

Connect to the new cluster

For non Apple Silicon machines

• In your terminal run the following to get the kubeconfig for the child cluster:

clusterctl get kubeconfig test1 > test.kubeconfig

• Then use it to explore the cluster:

kubectl --kubeconfig test.kubeconfig get pods -A

For Apple Silicon machines

• In your terminal run the following to get the kubeconfig for the child cluster:

kind get kubeconfig --name test1 > test.kubeconfig

• Then use it to explore the cluster:

kubectl --kubeconfig test.kubeconfig get pods -A

Scaling nodes

Lets scale the control plane to 3 nodes:

• Open 2 terminals
• In the first terminal watch the nodes of the child cluster:

kubectl --kubeconfig test.kubeconfig get nodes -w

For non Apple Silicon machines

• In the second terminal edit the control plane:

kubectl edit rke2controlplane/test1-control-plane

• In the editor find spec.replicas and change it to 3
• Save and exit from editor
• Watch the nodes being added to the child cluster

For Apple Silicon machines

• In the second terminal edit the control plane:

kubectl edit kubeadmcontrolplane/test1-control-plane

• In the editor find spec.replicas and change it to 3
• Save and exit from editor
• Watch the nodes being added to the child cluster

Clear up

• Delete the child cluster by running:

kubectl delete cluster test1

• Delete the management cluster by running:

kind delete cluster --name=capi-test