135-cluster-api.sh

# Source: https://gist.github.com/d8113b6f149583e1cf1614d76f2a4182

#####################################################################
# How To Create, Provision, And Operate Kubernetes With Cluster API #
# https://youtu.be/8yUDUhZ6ako                                      #
#####################################################################

# Referenced videos:
# - Should We Replace Docker Desktop With Rancher Desktop?: https://youtu.be/bYVfCp9dRTE

#########
# Setup #
#########

# Create a Kubernetes cluster with Ingress
# This demo was tested on Rancher Desktop, but it should work with any Kubernetes cluster
# Please watch https://youtu.be/bYVfCp9dRTE if you are not familiar with Rancher Desktop

# Install the CLI from https://cluster-api.sigs.k8s.io/user/quick-start.html#install-clusterctl

################
# DigitalOcean #
################

export DIGITALOCEAN_ACCESS_TOKEN=[...]

export DO_B64ENCODED_CREDENTIALS="$(\
    echo -n "$DIGITALOCEAN_ACCESS_TOKEN" \
    | base64 \
    | tr -d '\n')"

export DO_REGION=nyc1

# Replace `[...]` with the SSH key fingerprint (e.g., `18:9c:3d:5c:9d:b8:0e:6f:df:58:f2:20:dd:2d:5d:54`)
export DO_SSH_KEY_FINGERPRINT=[...]

export DO_CONTROL_PLANE_MACHINE_TYPE=s-2vcpu-2gb

export DO_NODE_MACHINE_TYPE=s-2vcpu-2gb

#################################
# Create Virtual Machine Images #
#################################

git clone https://github.com/kubernetes-sigs/image-builder

cd image-builder/images/capi

cat Makefile

make build-do-ubuntu-2004

# The command might fail asking you to install additional tools (e.g., Ansible)

doctl compute image list

export DO_CONTROL_PLANE_MACHINE_IMAGE=[...]

export DO_NODE_MACHINE_IMAGE=[...]

cd ../../../

###################################
# Setup Cluster API And Providers #
###################################

clusterctl init \
    --infrastructure digitalocean

###############################
# Create A Kubernetes Cluster #
###############################

clusterctl generate cluster devops-toolkit \
    --infrastructure digitalocean \
    --target-namespace infra \
    --kubernetes-version v1.20.10 \
    --control-plane-machine-count 3 \
    --worker-machine-count 3 \
    | tee cluster.yaml

kubectl create namespace infra

kubectl apply --filename cluster.yaml

kubectl --namespace infra \
    get clusters

kubectl --namespace infra \
    get machinedeployments

kubectl --namespace infra \
    get kubeadmcontrolplane

kubectl --namespace infra \
    describe kubeadmcontrolplane \
    devops-toolkit-control-plane

clusterctl --namespace infra \
    get kubeconfig devops-toolkit \
    | tee kubeconfig.yaml

kubectl --kubeconfig kubeconfig.yaml \
    apply \
    --filename https://docs.projectcalico.org/v3.20/manifests/calico.yaml

kubectl --kubeconfig kubeconfig.yaml \
    get nodes

#################################################
# Upgrade A Kubernetes Clsuter With Cluster API #
#################################################

kubectl --namespace infra \
    get kubeadmcontrolplane

cd image-builder/images/capi

# Replace `1.20.10` with `1.21.6` in `packer/config/kubernetes.json`
# Replace `1.20` with `1.21` in `packer/config/kubernetes.json`

make build-do-ubuntu-2004

doctl compute image list

# Copy the ID of the newly created image

cd ../../../

# Open `cluster.yaml`
# Copy `DOMachineTemplate` resource of the control plane
# Change the `image` of new `MachineTemplate` resources
# Save the changes

kubectl apply --filename cluster.yaml

# Open `cluster.yaml`
# Change the `name` of the `MachineTemplate` reference of the control plane
# Replace `v1.20.10` with `v1.21.6`
# Save the changes

kubectl apply --filename cluster.yaml

# Sometimes it works, sometimes it doesn't.

# Do the same for worker nodes

###########
# Destroy #
###########

kubectl delete --filename cluster.yaml

kubectl --namespace infra \
    get clusters

# Wait until the cluster is deleted

# Destroy or reset the management cluster