Vaibhav Parekh's Blog

Run the same code in your environment and try to launch more use cases of multi-tier websites.

Vaibhav Parekh's photo
Vaibhav Parekh
·

2 min read

Run the same code in your environment and try to launch more use cases of multi-tier websites.

In a Kubernetes environment, launching multi-tier websites involves creating several layers of services such as the frontend, backend, and database, all working together. Here’s how you can run a multi-tier website in a Kubernetes cluster:

Steps:

  1. Prepare the YAML files:

    • You’ll need to define the services, deployments, and persistent volume claims for each tier of your multi-tier application (frontend, backend, database).

  2. Setup your Kubernetes Cluster:

    • Ensure you have kubectl configured and a running Kubernetes cluster (either local or cloud-based like Google Kubernetes Engine (GKE) or Amazon Elastic Kubernetes Service (EKS)).

  3. Example Multi-tier Application Stack:

    • Frontend (Node.js, React, or any web framework)

    • Backend (Node.js, Django, Flask, etc.)

    • Database (MySQL, PostgreSQL)

Step-by-step guide

1. Frontend Service (Node.js):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: frontend-deployment
spec:
  replicas: 2
  selector:
    matchLabels:
      app: frontend
  template:
    metadata:
      labels:
        app: frontend
    spec:
      containers:
      - name: frontend
        image: your-frontend-image:latest
        ports:
        - containerPort: 80
---
apiVersion: v1
kind: Service
metadata:
  name: frontend-service
spec:
  selector:
    app: frontend
  ports:
  - protocol: TCP
    port: 80
    targetPort: 80
  type: LoadBalancer

2. Backend Service (Node.js/Django):

apiVersion: apps/v1
kind: Deployment
metadata:
  name: backend-deployment
spec:
  replicas: 2
  selector:
    matchLabels:
      app: backend
  template:
    metadata:
      labels:
        app: backend
    spec:
      containers:
      - name: backend
        image: your-backend-image:latest
        ports:
        - containerPort: 8080
        env:
        - name: DATABASE_URL
          value: "mysql://db-service:3306/dbname"
---
apiVersion: v1
kind: Service
metadata:
  name: backend-service
spec:
  selector:
    app: backend
  ports:
  - protocol: TCP
    port: 8080
    targetPort: 8080

3. Database (MySQL):

apiVersion: v1
kind: PersistentVolumeClaim
metadata:
  name: mysql-pvc
spec:
  accessModes:
    - ReadWriteOnce
  resources:
    requests:
      storage: 1Gi
---
apiVersion: apps/v1
kind: Deployment
metadata:
  name: db-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: db
  template:
    metadata:
      labels:
        app: db
    spec:
      containers:
      - name: mysql
        image: mysql:5.7
        env:
        - name: MYSQL_ROOT_PASSWORD
          value: password
        - name: MYSQL_DATABASE
          value: dbname
        ports:
        - containerPort: 3306
        volumeMounts:
        - name: mysql-storage
          mountPath: /var/lib/mysql
      volumes:
      - name: mysql-storage
        persistentVolumeClaim:
          claimName: mysql-pvc
---
apiVersion: v1
kind: Service
metadata:
  name: db-service
spec:
  ports:
  - port: 3306
  selector:
    app: db

4. Apply YAML Files:

kubectl apply -f frontend.yaml
kubectl apply -f backend.yaml
kubectl apply -f database.yaml

5. Testing Multi-Tier App:

Once the services are up and running, you can:

  • Access the frontend via the LoadBalancer IP (or port forward if using a local cluster).

  • The frontend will communicate with the backend, which will, in turn, interact with the database.

This setup allows you to host a multi-tier website with Kubernetes. Each component is independently scalable, and Kubernetes will ensure they are highly available and resilient.

DockerDevopsLinuxKubernetes