Live application deployement - K8s project | day 6 | Service, Custom Domain Ingress

Service in K8s:

In Kubernetes, a Service is a method for exposing a network application that is running as one or more Pods in your cluster.

Official docs to read:

https://kubernetes.io/docs/concepts/services-networking/service/

Defining a Service

A Service is an object (the same way that a Pod or a ConfigMap is an object). You can create, view or modify Service definitions using the Kubernetes API. Usually you use a tool such as kubectl to make those API calls for you.

For example, suppose you have a set of Pods that each listen on TCP port 9376 and are labelled as app.kubernetes.io/name=MyApp. You can define a Service to publish that TCP listener:

apiVersion: v1
kind: Service
metadata:
  name: my-service
spec:
  selector:
    app.kubernetes.io/name: MyApp
  ports:
    - protocol: TCP
      port: 80
      targetPort: 9376

What are the the problems with Deployments that we need to make Services?

Deployments handle scaling, updates, and Pod management but don’t ensure stable networking or external access. Pods have dynamic IPs that change upon restarts, making direct communication difficult. Services solve these issues by providing stable networking, consistent IPs, load balancing, and controlled external access.

Services solve these issues by:

• Providing a stable, unchanging IP or DNS name.
• Offering automatic load balancing to distribute traffic across multiple Pods.
• Enabling controlled external access options (e.g., ClusterIP for internal, LoadBalancer for external).

⇒ Services ensure reliable networking and stable access to applications, whether for internal communication or external user access.

kubectl create deploy day-6 --image=<docker-image-name>