Install Load Balancer

Install bare-metal Load Balancer service

note

Bare-metal ingress controller consideration

note

Metallb concept

Add Helm Chart repository:

helm repo add metallb https://metallb.github.io/metallb
helm repo update

Install metallb as a Load Balancer service:

helm install --create-namespace --namespace metallb metallb metallb/metallb

Configure Load Balancer iptool:

metallb-iptool.yaml

---
apiVersion: metallb.io/v1beta1
kind: IPAddressPool
metadata:
  name: default
  namespace: metallb
spec:
  addresses:
  - 10.10.10.240-10.10.10.245
  autoAssign: true
---
apiVersion: metallb.io/v1beta1
kind: L2Advertisement
metadata:
  name: default
  namespace: metallb
spec:
  ipAddressPools:
  - default

Apply the Load Balancer configuration:

kubectl apply -f metallb-iptool.yaml

Verify metallb deployment installation:

kubectl get -n metallb pods
kubectl logs -n metallb metallb-controller-<Tab>
helm list -n metallb

Intergrate metallb with NGINX Ingress Controller

note

Bare-metal consideration

danger

To complete this task, you need to first install the NGINX Ingress Controller from the previous chapter!

Tell NGINX Ingress Controller to stop using host network:

helm upgrade -n ingress-nginx ingress-nginx ingress-nginx/ingress-nginx --set controller.hostNetwork=false

Check NGINX Ingress Controller:

helm list -n ingress-nginx

Check the External IP of the NGINX Ingress Controller:

kubectl get svc -n ingress-nginx

Deploy test web application

Create a new namespace for the web application:

kubectl create namespace front-web

Create a new application in a specific namespace:

kubectl create deployment -n front-web web-app --image=nginx:1.23 --replicas=3

See created Deployment

apiVersion: apps/v1
kind: Deployment
metadata:
  creationTimestamp: null
  labels:
    app: web-app
  name: web-app
  namespace: front-web
spec:
  replicas: 3
  selector:
    matchLabels:
      app: web-app
  strategy: {}
  template:
    metadata:
      creationTimestamp: null
      labels:
        app: web-app
    spec:
      containers:
      - image: nginx:1.23
        name: nginx
        resources: {}
status: {}

Check deployment status:

kubectl get deploy,rs,pods -o wide -n front-web

Expose fronted application with service in mode LoadBalancer:

kubectl expose deployment -n front-web web-app --port=80 --type=LoadBalancer

See created Service

apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web-app
  name: web-app
  namespace: front-web
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: web-app
  type: LoadBalancer
status:
  loadBalancer: {}

Check Service status:

kubectl get svc -n front-web web-app

Output:

NAME      TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)        AGE
web-app   LoadBalancer   10.106.220.243   10.10.10.241  80:32586/TCP   7s

Try to connect from remote host:

curl http://10.10.10.241

Delete LoadBalancer service:

kubectl delete service -n front-web web-app

Expose once again web-app with ClusterIP:

kubectl expose deployment -n front-web web-app --type=ClusterIP --port=80

See created Service

apiVersion: v1
kind: Service
metadata:
  creationTimestamp: null
  labels:
    app: web-app
  name: web-app
  namespace: front-web
spec:
  ports:
  - port: 80
    protocol: TCP
    targetPort: 80
  selector:
    app: web-app
  type: ClusterIP
status:
  loadBalancer: {}

Check service object:

kubectl get svc -n front-web

Configure Ingress for web-app

front-web.yaml"

apiVersion: networking.k8s.io/v1
kind: Ingress
metadata:
  name: frontend-ingress
  namespace: front-web
  annotations:
    nginx.ingress.kubernetes.io/rewrite-target: /$1
spec:
  ingressClassName: "nginx"
  rules:
    - host: front-web.info
      http:
        paths:
          - path: /
            pathType: Prefix
            backend:
              service:
                name: web-app
                port:
                  number: 80

Apply Ingress configuration:

kubectl apply -f front-web.yaml

:Check EXTERNAL-IP for NGINX Ingress Controller:

kubectl get svc -n ingress-nginx ingress-nginx-controller

Output:

NAME                       TYPE           CLUSTER-IP       EXTERNAL-IP   PORT(S)                      AGE
ingress-nginx-controller   LoadBalancer   10.109.139.127   10.10.10.240  80:31801/TCP,443:31942/TCP   3h16m

Check connection to web-app:

curl -D- http://10.10.10.240 -H 'Host: front-web.info'

Clean up:

kubectl delete namespace front-web