K3s

These steps will add k3s kubernetes to your bowl. You should already have an ubuntu 20.04 server running from step 1.

Install k3s kubernetes

curl -sfL https://get.k3s.io | INSTALL_K3S_EXEC="--no-deploy traefik" sh -

The curl command downloads k3s & sh - runs the installer.

The K3S_KUBECONFIG_MODE install option makes the kube config file accessible to non-admins. It’s a shortcut for this workshop and wouldn’t be used in production. You’ll see a couple of warnings about this later- but for a lab environment it’s just fine.

Export the KUBE config file for later.

Create a folder to save your KUBE config.

mkdir ~/.kube

Set permissions to allow your account only (this prevents security warnings later).

sudo chmod -R 700  ~/.kube

Exporting the config allows kubernetes to find your installation.

sudo cp /etc/rancher/k3s/k3s.yaml ~/.kube/config

We’re copying the k3s yaml file to a location you can access without needing to run sudo every time.

Ensure you have access to the exported config file.

sudo chown -R $USER ~/.kube

We’re setting the owner of the .kube folder and everything inside it (recursively with -R) to you ($USER).

Install Kubecontrol

Download.

curl -LO https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl

Install.

sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl

grant access to k3s kubectl: sudo k3s kubectl get pods -A

kubecontrol is the controller manager for kubernetes. We’ll use it through the workshop for adding/changing the kubernetes installation. Similar to before, curl downloads the software and launches a bash shell for installation.

(todo) update HELM?

helm repo add nginx-stable https://helm.nginx.com/stable helm repo add nginx https://kubernetes.github.io/ingress-nginx helm install nginx nginx/ingress-nginx –set controller.hostNetwork=true,controller.service.type=”“,controller.kind=DaemonSet helm install nginx nginx-stable/nginx-ingress –set controller.kind=DaemonSet –set controller.hostNetwork=true –set controller.service.create=false –set controller.enableLatencyMetrics=false –set prometheus.create=false –set controller.hostPort=true helm install cert-manager jetstack/cert-manager –namespace cert-manager –create-namespace –set installCRDs=true

helm repo add ingress-nginx https://kubernetes.github.io/ingress-nginx helm repo update helm install ingress-nginx ingress-nginx/ingress-nginx

taint: kubectl taint node [node] node-role.kubernetes.io/master:NoSchedule-

DNS UTILS

kubectl apply -f https://k8s.io/examples/admin/dns/dnsutils.yaml kubectl exec -i -t dnsutils – nslookup kubernetes.default

ALL logs kubectl logs –namespace=kube-system -l k8s-app=kube-dns

CHECKPOINT

Run kubectl get nodes and ensure you see a ‘ready’ response for your control-plane. If you get an error, it’s typically a miss on on exporting the configuration.

Next Steps

If kubernetes is up and running, Congratulations! You’re well on your way to a full-featured Kubernetes installation. Let’s add Rancher in Step 3.

Recycling this ingredient

Run the command below to remove kubernetes.

/usr/local/bin/k3s-uninstall.sh

K3s

Login to your ubuntu server