Kubernetes Handbook

Kubernetes handbook, this repo utilizes Tencent Cloud K3S as the demo environment

You should already have a K3S/miniKube/K8S env with kubectl and envsubst as precondition

Install

Set Kube Config

By default, $HOME/.kube might exist an config and you do not need config it

[Optional]

1. Edit /etc/profile, you may need sudo to add

export KUBECONFIG=/etc/rancher/k3s/k3s.yaml

For lighthouse user, you may need to add KUBECONFIG in .bashrc

You can exit Vim by :wq!

In Tencent Cloud, you might not be able to leave Insert Mode
Please press Ctrl + Shift + F5
Or use Ctrl + C to force Command Mode
Or maybe you are in Record Mode, press Q to finish

2. Apply

source /etc/profile

You can check if it works by echo $KUBECONFIG

You can set env EMAIL and DOMAIN for later use according to step 1:

export EMAIL=xxx.xxx@gmail.com
export DOMAIN=xxx.com

Install Helm

curl https://raw.githubusercontent.com/helm/helm/main/scripts/get-helm-3 | bash

Add Helm Repo

helm repo add jetstack https://charts.jetstack.io && helm repo update

Cert

Install Cert-Manager

1. Create namespace

kubectl create namespace cert-manager

2. Install cert-manager

Check installeable version

helm search repo cert-manager

helm install \
  cert-manager jetstack/cert-manager \
  --namespace cert-manager \
  --set installCRDs=true

--set installCRDs=true : For ClusterIssuer later
--version v1.xx.x ：You can specify an old version

3. [Optional] Install CRD

Skip this step ff you already set installCRDs in previous

Manual install CRD

Check installed version

helm list -n cert-manager

Apply the yaml, REMEMBER to replace the version number!!!

kubectl apply --validate=false -f https://github.com/jetstack/cert-manager/releases/download/v1.14.5/cert-manager.yaml

This step could be also used for installation without helm

4. [Optional] Check Running Pods

kubectl get pods --namespace cert-manager

Config ClusterIssuer

Refer to K3S Rocks

1. Add ClusterIssuer

letsencrypt-prod.yaml

apiVersion: cert-manager.io/v1
kind: ClusterIssuer
metadata:
  name: letsencrypt-prod
spec:
  acme:
    email: $EMAIL    # Email Address
    server: https://acme-v02.api.letsencrypt.org/directory
    privateKeySecretRef:
      name: letsencrypt-prod
    solvers:
    - http01:
        ingress:
          class: traefik
---

2. Add Middleware

traefik-https-redirect-middleware.yaml

apiVersion: traefik.containo.us/v1alpha1
kind: Middleware
metadata:
  name: redirect-https
spec:
  redirectScheme:
    scheme: https
    permanent: true
---

3. Add Ingress

whoami-ingress-tls.yaml

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: whoami-tls-ingress
  annotations:
    spec.ingressClassName: traefik
    cert-manager.io/cluster-issuer: letsencrypt-prod
    traefik.ingress.kubernetes.io/router.middlewares: default-redirect-https@kubernetescrd
    # default is Namespace, redirect-https is Middleware name
spec:
  rules:
    - host: whoami.$DOMAIN        # Domain name
      http:
        paths:
          - path: /
            pathType: Prefix      # Prefix | ImplementationSpecific
            backend:
              service:
                name: whoami-svc  # Service name
                port:
                  number: 8888    # Service port, not pod port
  tls:
    - secretName: whoami-tls      # Certificate name
      hosts:
        - whoami.$DOMAIN          # Domain name
---

4. Add Service

nginx-service.yaml

apiVersion: v1
kind: Service
metadata:
  labels:
    app: nginx-app
  name: whoami-svc
  namespace: default
spec:
  ports:
    - port: 8888        # Service port
      protocol: TCP
      name: app-port
      targetPort: 80
  type: ClusterIP
  selector:
    app: nginx-app
---

5. Add Deployment

nginx-deployment.yaml

apiVersion: apps/v1
kind: Deployment
metadata:
  name: nginx-deployment
spec:
  selector:
    matchLabels:
      app: nginx-app
  replicas: 2 # Tells deployment to run 2 pods matching the template
  template:
    metadata:
      labels:
        app: nginx-app
    spec:
      containers:
      - name: nginx-app
        image: nginx:1.26.0
        ports:
        - containerPort: 80
---

Deployment

Check Deployment

cat *.yaml | envsubst

Check if DOMAIN and EMAIL is correctly filled

Apply Deployment

cat *.yaml | envsubst | kubectl apply -f -

Each yaml file should have a separator --- with line break in the end, otherwise it cannot be parsed

Delete Deployment

kubectl delete all -l app=nginx-app

delete all will not delete ingress,configmap,etc.

Done

Now, you can check the welcome page by:

https://whoami.$DOMAIN/