What is Ingress in Kubernetes

First thing to discuss is whats is the difference between Service and Ingress? What is the difference between two?

Lets start with a simple scenario.

We are working on an application and that has an online store selling products. It is available at my-online-store.com. It s built into a Docker image and deployed on a Kubernetes cluster as POD in a deployment. We need a database and we deployed MySQL database as a POD and created a service of type cluster IP called MySQL service to make it accessible to the application.