10 days back I was given a task to deploy two applications in kubernetes.

Acceptence criteria

• Apps should be accessible using endpoints
• Separate deployments for dev and qa
• Follow GitOps approach
• One app needs to access the RDS database
• Use AWS EKS

So lets finish this task starting from scratch and learn along the way.

🤔 Where to start from?

All we got are two apps and a database. Lets get ourselves a kubernetes cluster.

1. Create k8s cluster 🚀

• Go to AWS EKS console

  • Create cluster
  • Name -> my-first-eks
  • Version -> default

  • Role

    • Create Role
    • Service -> EKS -> EKS Cluster
    • Name -> my-first-eks
  • Default for VPC and networking
  • Create node group
  • Name -> my-first-eks-node-group

  • Role

    • Create Role
    • Name -> my-first-eks-node-role
    • Permissions
    • AmazonEC2ContainerRegistryReadOnly
    • AmazonEKSCNIPolicy
    • AmazonEKSWorkerNodePolicy
    • Scaling
    • Desired: 1
    • Min: 1
    • Max: 1

2. Setup kubectl

Now that we have a cluster, lets connect to it using kubectl

kubectl is your primary tool to interact with kubernetes cluster.

• Download and install

  curl -LO "https://dl.k8s.io/release/$(curl -L -s https://dl.k8s.io/release/stable.txt)/bin/linux/amd64/kubectl"
  
  sudo install -o root -g root -m 0755 kubectl /usr/local/bin/kubectl
  

• Setup kubeconfig

  • Followed this 👉 AWS documentation

  aws sts get-caller-identity
  aws eks update-kubeconfig --region region-code --name my-cluster
  

  The above command will create a file ~/.kube/config with the cluster details.

• Verify by listing pods
  kubectl get pods -A

• [Optional] Add shell completions

  • For zsh, add following to the .zshrc file and restart the shell
    source <(kubectl completion zsh)

3. My first k8s deployment 🚀

Now lets get our hands dirty and deploy our first app.

• Create a deployment

  • Create a file deployment.yaml with the following content

  apiVersion: apps/v1
  kind: Deployment
  metadata:
  name: my-first-deployment
  spec:
  replicas: 1
  selector:
      matchLabels:
      app: my-first-deployment
  template:
      metadata:
      labels:
          app: my-first-deployment
      spec:
      containers:
          - name: my-first-deployment
          image: nginx:latest
          ports:
              - containerPort: 80
  

  • Apply the deployment
    kubectl apply -f deployment.yaml
  • Verify the deployment
    kubectl get deployments

• Create a service

  • Create a file service.yaml with the following content

    apiVersion: v1
    kind: Service
    metadata:
        name: my-first-service
    spec:
        ports:
        - port: 80
            targetPort: 80
            protocol: TCP
        selector:
            app: my-first-deployment
    

  • Apply the service
    kubectl apply -f service.yaml
  • Verify the service
    kubectl get services

• Accessign the app

  • Forward the port

    • kubectl port-forward svc/my-first-service 8080:80
  • Now you can access the app
    at http://localhost:8080

4. Tools

Couple of tools that I used in my first week of kubernetes

1. k9s
2. kubens
3. kubectx
4. VS Code Kubernetes extension by Microsoft

5. Argo CD 🚀

• Install ArgoCD

  kubectl create namespace argocd
  kubectl apply -n argocd -f https://raw.githubusercontent.com/argoproj/argo-cd/stable/manifests/install.yaml
  

• Configure port forwarding
  kubectl port-forward svc/argocd-server -n argocd 8080:443

• Access the UI

  • https://localhost:8080
  • Credentials
  • Username: admin

  • Password: use below command

    • kubectl get secret argocd-initial-admin-secret -n argocd -o jsonpath="{.data.password}" | base64 -d; echo

---

Link:

• Get to know Kubernetes

  • Kubernetes Crash Course for Absolute Beginners

| HIH
| Take care
~ @raevilman