Deploying a Web App with Persistent Storage in Kubernetes: PV, PVC, Pod & NodePort Explained

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Ques:- 

DevOps team is working on a Kubernetes template to deploy a web application on the cluster. There are some requirements to create/use persistent volumes to store the application code, and the template needs to be designed accordingly. Please find more details below:

Create a PersistentVolume named as pv-xfusion. Configure the spec as storage class should be manual, set capacity to 3Gi, set access mode to ReadWriteOnce, volume type should be hostPath and set path to /mnt/security .

Create a PersistentVolumeClaim named as pvc-xfusion. Configure the spec as storage class should be manual, request 3Gi of the storage, set access mode to ReadWriteOnce.

Create a pod named as pod-xfusion, mount the persistent volume you created with claim name pvc-xfusion at document root of the web server, the container within the pod should be named as container-xfusion using image nginx with latest tag only (remember to mention the tag i.e nginx:latest).

Create a node port type service named web-xfusion using node port 30008 to expose the web server running within the pod.

Ans:-

Here's a complete Kubernetes YAML template that fulfills all the requirements you've listed:

Note:- We have used Init container for:-

This container will automatically create an index.html file inside the mounted volume before the Nginx container starts.
 

The initContainer runs first and writes an HTML file to the volume.

The Nginx container then serves this file from /usr/share/nginx/html.

---

#PersistentVolume (pv-xfusion)

apiVersion: v1

kind: PersistentVolume

metadata:

  name: pv-xfusion

spec:

  storageClassName: manual

  capacity:

    storage: 3Gi

  accessModes:

    - ReadWriteOnce

  hostPath:

    path: /mnt/security

---

#PersistentVolumeClaim (pvc-xfusion)

apiVersion: v1

kind: PersistentVolumeClaim

metadata:

  name: pvc-xfusion

spec:

  storageClassName: manual

  accessModes:

    - ReadWriteOnce

  resources:

    requests:

      storage: 3Gi

---

#Pod (pod-xfusion) with volume mounted at web server root and Init container 

apiVersion: v1

kind: Pod

metadata:

  name: pod-xfusion

  labels:

    app: pod-xfusion

spec:

  initContainers:

    - name: init-xfusion

      image: busybox

      command: ['sh', '-c', 'echo "<h1>Hello from Raj Gupta!</h1>" > /mnt/security/index.html']

      volumeMounts:

        - mountPath: /mnt/security

          name: xfusion-storage

  containers:

    - name: container-xfusion

      image: nginx:latest

      volumeMounts:

        - mountPath: /usr/share/nginx/html

          name: xfusion-storage

  volumes:

    - name: xfusion-storage

      persistentVolumeClaim:

        claimName: pvc-xfusion

---

#NodePort Service (web-xfusion) on port 30008

apiVersion: v1

kind: Service

metadata:

  name: web-xfusion

spec:

  type: NodePort

  selector:

    # Ensure this matches the pod's labels if you add any

    # For now, we assume no labels, so selector will match pod name

    # Alternatively, you can add a label to the pod and match it here

    app: pod-xfusion

  ports:

    - protocol: TCP

      port: 80

      targetPort: 80

      nodePort: 30008

Conclusion:-

Learn how to deploy a web application on a Kubernetes cluster using PersistentVolumes and PersistentVolumeClaims to store application data. This hands-on tutorial walks you through:

• Creating a PersistentVolume (pv-xfusion) using hostPath
• Defining a PersistentVolumeClaim (pvc-xfusion) with storage class manual
• Deploying an Nginx pod (pod-xfusion) with volume mounted at the web server root
• Automating content creation using an initContainer
• Exposing the pod using a NodePort service (web-xfusion) on port 30008

By the end of this video, you'll understand how to manage persistent storage and expose services in Kubernetes effectively.