How do I set up Tomcat with Kubernetes in digitalocean?

Question

Hello, I already know how to set up tomcat and ssl on a standalone server, but I would like to learn cloud computing with Digitalocean. Is there a way to have a pod with Tomcat and ssl using kubernetes? In digitalocean how do I manage such deployment? so far I am documenting myself with the following docs:https://www.digitalocean.com/community/tutorial-collections/how-to-install-apache-tomcat https://docs.digitalocean.com/products/kubernetes/how-to/create-clusters/

Bobby Iliev · Answer

Hi there! 👋

It’s awesome to hear you’re diving into Kubernetes and cloud computing with DigitalOcean!

Here is a quick overview on how you could do that:

Step 1: Set Up Your Kubernetes Cluster

Start by creating a Kubernetes cluster in DigitalOcean.
- Follow this guide to get started: 👉 Create a Kubernetes Cluster in DigitalOcean

Once the cluster is ready, download your kubeconfig file and connect to the cluster:

doctl kubernetes cluster kubeconfig save <cluster-name>
kubectl get nodes  # To verify the connection

Step 2: Create a Deployment for Tomcat (or Your Custom Docker Image)

If you’re using the default Tomcat image, your Deployment YAML might look like this:

apiVersion: apps/v1
kind: Deployment
metadata:
  name: tomcat-deployment
spec:
  replicas: 1
  selector:
    matchLabels:
      app: tomcat
  template:
    metadata:
      labels:
        app: tomcat
    spec:
      containers:
      - name: tomcat
        image: tomcat:10-jdk17  # Use the default Tomcat image
        ports:
        - containerPort: 8080

Using Your Custom Docker Image: If you’ve built your own Docker image (e.g., registry.digitalocean.com/<your-repo>/custom-tomcat:latest), replace the image field with your image name:
```
containers:
- name: tomcat
  image: registry.digitalocean.com/<your-repo>/custom-tomcat:latest
  ports:
  - containerPort: 8080
```
Make sure your custom image is pushed to the DigitalOcean Container Registry (or any other accessible registry). Here’s how to push your image to DigitalOcean:
```
docker tag custom-tomcat:latest registry.digitalocean.com/<your-repo>/custom-tomcat:latest
docker push registry.digitalocean.com/<your-repo>/custom-tomcat:latest
```

Apply the Deployment:

kubectl apply -f tomcat-deployment.yaml

Step 3: Expose Tomcat with a Service

Create a Service to expose Tomcat on port 8080:

apiVersion: v1
kind: Service
metadata:
  name: tomcat-service
spec:
  type: LoadBalancer
  selector:
    app: tomcat
  ports:
  - protocol: TCP
    port: 80
    targetPort: 8080

Apply the Service:

kubectl apply -f tomcat-service.yaml

This will provision a DigitalOcean Load Balancer for your Tomcat pod. You can check the assigned external IP with:

kubectl get svc tomcat-service

Step 4: Add SSL with Cert-Manager

To set up SSL, I highly recommend using Cert-Manager, which simplifies certificate management. It’s available as a one-click app in the DigitalOcean Marketplace: 👉 Cert-Manager Guide

Once installed, configure an Ingress to use the certificate. Cert-Manager will handle the automatic provisioning and renewal of Let’s Encrypt certificates for you.

Let me know if you have any questions! 🚀

- Bobby