Jump right into Kubernetes development with career-focused lessons and hands-on practice.

DevOps for Developers

Kubernetes is a powerful container management tool that's taking the world by storm. This detailed course will help you master it.

In this course, you'll start with the fundamentals of Kubernetes and what the main components of a cluster look like. You'll then learn how to use those components to build, test, deploy, and upgrade applications, as well as how to achieve state persistence once your application is deployed. You'll also learn how to secure your deployments and manage resources, which are crucial DevOps skills.

By the time you're done, you'll have a firm grasp on what Kubernetes is, as well as the skills to deploy your own clusters and applications with confidence.

A Practical Guide to Kubernetes

# Defining an Ingress resource

We'll try to make our `go-demo-2-api` Service available through port `80`. We'll do that by defining an Ingress resource with the rule to forward all requests with the path starting with `/demo` to the Service `go-demo-2-api`.





## Looking into the definition
Let's look at the Ingress' YAML definition `go-demo-2-ingress.yml`:





apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: go-demo-2
  annotations:
    kubernetes.io/ingress.class: "nginx"
    ingress.kubernetes.io/ssl-redirect: "false"
    nginx.ingress.kubernetes.io/ssl-redirect: "false"
spec:
  rules:
  - http:
      paths:
      - path: /demo
        pathType: ImplementationSpecific
        backend:
          service:
            name: go-demo-2-api
            port:
              number: 8080


* **Line 5:** This time, `metadata` contains a field we haven't used before. The `annotations` section allows us to provide additional information to the Ingress controller. As you'll see soon, the Ingress API specification is concise and limited. That is done on purpose. The specification API defines only the fields that are mandatory for all Ingress controllers. All the additional information an Ingress controller needs is specified through `annotations`. That way, the community behind the controllers can progress at great speed while still providing basic general compatibility and standards.

>**Note:**  The list of general annotations and the controllers that support them can be found on the [Ingress Annotations](https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/annotations.md) page. For those specific to the [NGINX Ingress controller](https://github.com/kubernetes/ingress-nginx/blob/master/README.md), please visit the [NGINX Annotations](https://github.com/kubernetes/ingress-nginx/blob/master/docs/user-guide/nginx-configuration/annotations.md) page, and for those specific to GCE Ingress, visit the [ingress-gce](https://github.com/kubernetes/ingress-gce) page.

>**Note:**  You’ll notice that the documentation uses `nginx.ingress.kubernetes.io/` annotation prefixes. This is a relatively recent change that, at the time of this writing, applies to the beta versions of the controller. We combine it with `ingress.kubernetes.io/` prefixes so that the definitions work in all Kubernetes versions.

* **Line 8:** We specify the `nginx.ingress.kubernetes.io/ssl-redirect: "false"` annotation which tells the controller that we do not want to redirect all HTTP requests to HTTPS. We’re forced to do so since we do not have SSL certificates for the exercises that follow.

Now that we have understood `metadata` and `annotations`, we can move to the `ingress` specification.

* **Line 9--19:** We specify a set of `rules` in the `spec` section. They are used to configure Ingress resources. For now, our rule is based on `http` with a single `path` and a `backend`. All the requests with the `path` starting with `/demo` will be forwarded to the service `go-demo-2-api` on port `8080`.

# Creating the resource
Now that we’ve had a short tour of some of the Ingress configuration options, we can proceed and create the resource.

Understand the definition of an Ingress resource and then create the objects based on this definition.

Creating Ingress Resources Based on Paths

Defining an Ingress resource

Looking into the definition