nginx_ingress_lab.md

Set up Nginx Ingress Controller for Traffic Routing

Install helm to setup Nginx Ingress Controller. To install helm version 3 on Linux or MacOS, you can follow following instructions.

curl https://raw.githubusercontent.com/helm/helm/master/scripts/get-helm-3 | bash

You could further refer to Official HELM Install Instructions for alternative options.

Verify the installtion is successful,

helm --help
helm version

Launch Nginx Ingress controller using helm as :

helm upgrade --install ingress-nginx ingress-nginx \
  --repo https://kubernetes.github.io/ingress-nginx \
  --namespace ingress-nginx --create-namespace \
  --set controller.hostPort.enabled=true \
  --set controller.service.type=NodePort \
  --set controller.hostPort.ports.http=80 \
  --set-string controller.nodeSelector."kubernetes\.io/os"=linux \
  --set-string controller.nodeSelector.ingress-ready="true"

Check the pod for Nginx Ingress, if its running

kubectl get pods -n ingress-nginx

You may see the pod in pending state. Check why its pending by describing it.

Once you describe, you will see that its pending because it has a nodeSelector defined which is looking for a node with label set to ingress-ready="true".

Check the label on the current nodes

kubectl get nodes --show-labels

Add this lable to first of the worker nodes as

kubectl label node kind-worker ingress-ready="true"

validate

kubectl get nodes --show-labels

This time you should see the label added, and nginx ingress controller running, which can be validated using

kubectl get pods -n ingress-nginx --watch

Wait for the container for nginx ingress controller to be up. You could also validate by connecting to the IPADDRESS of your node where the cluster is beeng setup on port 80, where you should see **404 Not Found** error. This is the sign that nginx is set up as a ingress controller and looking for a request with hostname/path defined.

Create Ingress Rule

File vote-ing.yaml

---
apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: vote
  namespace: instavote
spec:
  ingressClassName: nginx
  rules:
  - host: vote.example.com
    http:
      paths:
      - path: /
        pathType: Prefix
        backend:
          service:
            name: vote
            port:
              number: 80

apply

kubectl apply -f vote-ing.yaml

validate

kubectl get ing 
kubectl describe ing vote 

Add Local DNS

You have created the ingress rules based on hostnames e.g. vote.example.com and results.example.com. In order for you to be able to access those, there has to be a dns entry pointing to your nodes, which are running traefik.

  vote.example.com     -------+                        +----- vote:81
                              |     +-------------+    |
                              |     |   ingress   |    |
                              +===> |   node:80   | ===+
                              |     +-------------+    |
                              |                        |
  results.example.com  -------+                        +----- results:82

To achieve this you need to either,

• Create a DNS entry, provided you own the domain and have access to the dns management console.
• Create a local hosts file entry. On unix systems its in /etc/hosts file. On windows its at C:\Windows\System32\drivers\etc\hosts. You need admin access to edit this file.

For example, on a linux or osx, you could edit it as,

sudo vim /etc/hosts

And add an entry such as ,

xxx.xxx.xxx.xxx vote.example.com results.example.com  kube-ops-view.example.org

where,

• xxx.xxx.xxx.xxx is the actual IP address of one of the nodes running traefik.

And then access the app urls using http://vote.example.com