Kubernetes

Day 5: Kubernetes Services — How Your App Gets a Stable IP or URL

By now, you’ve launched a container, wrapped it in a Pod, deployed it using a Deployment, and scaled it up to multiple Pods.

But here’s the next problem:

“Okay, my app is running inside Kubernetes… but how do I access it?”

You try running:

kubectl get pods -o wide

And you see something like:

NAME       READY   STATUS    IP            NODE
myapp-xyz  1/1     Running   10.244.1.5    worker-node-1

Great — but:

That’s where Services come in.

What Is a Kubernetes Service?

A Service is a stable way to access one or more Pods.

You can think of it as:

You attach a Service to a set of Pods using labels
The Service tracks the matching Pods — even as Pods come and go
Kubernetes uses something called kube-proxy to route traffic to the correct Pod behind the scenes

So even if Pods restart, the Service endpoint never changes.

Let’s say you run 3 Pods of a web app with the label:

app: myapp

You create a Service like this:

selector:
  app: myapp

Now, when someone accesses the Service:

Type	Use Case	Accessible From
ClusterIP (default)	Internal communication	Inside the cluster only
NodePort	Basic external access	Outside the cluster (via IP:port)
LoadBalancer	Cloud environments	Public IP from cloud provider
ExternalName	Maps to external DNS	For external services

Imagine your app’s Pods are like food trucks moving around a festival ground.

A Service is like the signpost that says:

🍔 “Burgers this way →”

You don’t care where the trucks are parked — you just follow the sign. Kubernetes routes you to the right place, even if trucks come and go.

Use the Kubernetes Playground:
👉 KodeKloud Kubernetes Playground

Create a deployment:

kubectl create deployment myapp --image=nginx
kubectl expose deployment myapp --port=80 --type=NodePort
kubectl get service

Now run:

kubectl get pods -o wide
kubectl describe service myapp

Look for the NodePort (e.g., 30123) and try opening:

http://<worker-node-ip>:30123

You’re now accessing your app through a Kubernetes Service!

Pods have dynamic IPs and can restart anytime
A Service gives your app a stable endpoint
Services load-balance traffic to healthy Pods
You can expose your app internally or externally with different service types