--- title: "Deploy and Test a Load Balancer with Nginx | Hostman Docs" description: "Step-by-step guide on creating an Nginx deployment behind a Kubernetes load balancer and verifying traffic distribution between pods." --- > For the complete documentation index for AI agents, see [llms.txt](https://hostman.com/llms.txt). To demonstrate the functionality of a load balancer, we will create two Nginx deployments, each displaying its own HTML page. The load balancer will distribute requests randomly between the pods, showing one of the pages depending on which pod is selected. ## Environment Setup To simplify management and allow quick removal of all resources associated with the load balancer, we will create a separate namespace. This makes testing and resource cleanup easier while keeping the main cluster clean. Run the following command to create the namespace: ```shell kubectl create namespace test-namespace ``` After creation, use this namespace for all subsequent resources, including the load balancer, deployments, and `ConfigMap`. To do this, add the line `namespace: test-namespace` to every manifest related to the example. ## Create a ConfigMap for HTML Pages We will start by creating a `ConfigMap` to store two HTML pages. Pod 1 will display a page with the heading "Pod 1," and Pod 2 will display a page with the heading "Pod 2." These pages will be connected to Nginx within the pods. `nginx-pages-configmap.yaml`: ```yml apiVersion: v1 kind: ConfigMap metadata: name: nginx-pages namespace: test-namespace data: index-page1.html: |

Pod 1

This is page served by Pod 1.

index-page2.html: |

Pod 2

This is page served by Pod 2.

``` Here we create a `ConfigMap` with two HTML files: `index-page1.html` and `index-page2.html`. These files will be mounted into Nginx pods, allowing each pod to display its specific page. Apply the `ConfigMap`: ```shell kubectl apply -f nginx-pages-configmap.yaml ``` ## Create Nginx Deployments Next, we create two deployments, each using different HTML pages from the `ConfigMap`. The deployments use the selector `app: nginx`, which the load balancer will use to identify pods participating in traffic distribution. `nginx-deployment-pod1.yaml`: ```yml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-pod1 namespace: test-namespace spec: replicas: 1 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:latest volumeMounts: - name: nginx-pages mountPath: /usr/share/nginx/html/index.html subPath: index-page1.html ports: - containerPort: 80 volumes: - name: nginx-pages configMap: name: nginx-pages ``` This deployment creates a single pod (replica 1) with the Nginx image, which mounts the `index-page1.html` file from the `ConfigMap` into the directory `/usr/share/nginx/html/index.html`. Port 80 is open for accessing the page. Apply the deployment: ```shell kubectl apply -f nginx-deployment-pod1.yaml ``` `nginx-deployment-pod2.yaml`: ```yml apiVersion: apps/v1 kind: Deployment metadata: name: nginx-pod2 namespace: test-namespace spec: replicas: 1 selector: matchLabels: app: nginx template: metadata: labels: app: nginx spec: containers: - name: nginx image: nginx:latest volumeMounts: - name: nginx-pages mountPath: /usr/share/nginx/html/index.html subPath: index-page2.html ports: - containerPort: 80 volumes: - name: nginx-pages configMap: name: nginx-pages ``` This deployment also creates an Nginx pod but mounts the `index-page2.html` file, which has different content. Apply the second deployment: ```shell kubectl apply -f nginx-deployment-pod2.yaml ``` ## Configure the Load Balancer Now, create a load balancer that will direct requests to pods with the label `app: nginx`. `nginx-loadbalancer.yaml`: ```yaml apiVersion: v1 kind: Service metadata: name: nginx-loadbalancer namespace: test-namespace spec: selector: app: nginx ports: - port: 80 targetPort: 80 appProtocol: k8s.hostman.com/proto-http type: LoadBalancer ``` In this `Service`, we specify `type: LoadBalancer`, which creates a load balancer, and `selector: app: nginx`, which directs requests to the Nginx pods from our deployments. Requests to the load balancer are distributed among the pods using the `roundrobin` algorithm, which is the default. Apply the load balancer: ```shell kubectl apply -f nginx-loadbalancer.yaml ``` ## Verify the Load Balancer After creating the load balancer, you can find its public IP address in the dashboard or by running the command: ```shell kubectl get services -n test-namespace ``` Accessing this IP address will display a page served by one of the pods. Each time you refresh the page, traffic may be redirected to different pods, allowing the load balancer to switch the displayed page randomly. ## Deleting Resources After Testing Once you have verified the load balancer’s functionality, you can delete all the created pods and resources. Use the following commands: ```shell kubectl delete service nginx-loadbalancer -n test-namespace kubectl delete deployment nginx-pod1 -n test-namespace kubectl delete deployment nginx-pod2 -n test-namespace kubectl delete configmap nginx-pages -n test-namespace ``` These commands will remove the load balancer, pod deployments, and the `ConfigMap` created earlier. Alternatively, delete the entire namespace: ```shell kubectl delete namespace test-namespace ``` This method will automatically remove all resources associated with the test environment.