Complete Guide to Deploying PHP Applications on Kubernetes

In today’s fast-evolving tech landscape, Kubernetes has emerged as the leader in container orchestration. It offers developers powerful tools to easily deploy PHP applications. This guide will walk you through the steps to deploy PHP applications on Kubernetes, helping you get started quickly and manage your app efficiently.

Overview of Kubernetes

Kubernetes is an open-source container orchestration platform that provides automation for deploying, scaling, and managing containerized applications. Whether in the cloud or on-premises, Kubernetes enables efficient application operation across clusters.

Preparation Before Deployment

Before deploying a PHP application, you need to complete the following preparation steps:

Install Kubernetes

Make sure Kubernetes is installed and properly configured on your computer or server. You can use tools like Minikube or Kubeadm to set up a local installation of Kubernetes.

Install kubectl Command Line Tool

Install the kubectl tool to interact with the Kubernetes API. The detailed installation steps can be found in Kubernetes’ official documentation.

Create a PHP Application

Before deploying, you need to prepare a simple PHP application. Here’s an example of basic PHP code:

echo "Hello, Kubernetes!";

Build the Docker Image

In a Kubernetes environment, applications usually run inside containers. Therefore, you need to package your PHP application into a Docker image. Create a file named Dockerfile with the following content:

FROM php:7.4-apache
COPY . /var/www/html/

In the directory containing the Dockerfile, run the following command to build the Docker image:

docker build -t my-php-app .

Push the Docker Image to a Repository

Next, push the built Docker image to a public or private image repository (like Docker Hub). Use the following commands to log in and push your image:

docker login
 docker tag my-php-app your-dockerhub-username/my-php-app
 docker push your-dockerhub-username/my-php-app

Create Kubernetes Deployment File

To deploy the application on Kubernetes, you need to create a deployment configuration file (e.g., deployment.yaml). Here’s an example of the deployment file content:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: my-php-app
spec:
  replicas: 2
  selector:
    matchLabels:
      app: my-php-app
  template:
    metadata:
      labels:
        app: my-php-app
    spec:
      containers:
      - name: my-php-app
        image: your-dockerhub-username/my-php-app
        ports:
        - containerPort: 80

Then run the following command to create the deployment:

kubectl apply -f deployment.yaml

Expose the PHP Application

To make your PHP application accessible externally, you need to create a service configuration file (e.g., service.yaml). Here’s an example of the service file content:

apiVersion: v1
kind: Service
metadata:
  name: my-php-app
spec:
  type: LoadBalancer
  ports:
  - port: 80
  selector:
    app: my-php-app

Run the following command to create the service:

kubectl apply -f service.yaml

Access the PHP Application

Once the steps above are completed, you can access your PHP application via the external IP provided by Kubernetes. Use the following command to get service details:

kubectl get services

Conclusion

By following this guide, you’ve successfully deployed a PHP application in a Kubernetes environment. You’ve learned how to build and push Docker images, as well as how to deploy and expose applications in Kubernetes. As you dive deeper into Kubernetes, you'll be able to better manage and scale your PHP applications.