# Load Balancers

Load Balancers are essential when running a service. They expose the containers and images in which your application resides. When your containers are run inside a private network, you need a load balancer to listen on the correct ports to access the application. DuploCloud integrates seamlessly with Azure Load Balancers to expose Kubernetes services or Docker containers.

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DuploCloud allows no more than one (1) Load Balancer per DuploCloud Service.
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## **Prerequisites**

Before adding a Load Balancer, you need to create the necessary services:

* **For Kubernetes**: See the DuploCloud documentation for [creating an AKS Service](https://docs.duplocloud.com/docs/automation-platform/overview-2/containers-and-services/aks-containers-and-services#creating-a-duplocloud-aks-service).
* **For Docker**: Ensure Docker containers are set up and accessible within your infrastructure. For detailed instructions, see the [DuploCloud documentation](https://docs.duplocloud.com/docs/automation-platform/overview-2/docker-web-application#id-2-toc-title).

To create a **Shared Application Gateway** Load Balancer, refer to the [Shared Application Gateway](https://docs.duplocloud.com/docs/automation-platform/kubernetes-overview/ingress-loadbalancer/aks-ingress) documentation

## Adding a Load Balancer

1. In the DuploCloud Portal, navigate to:
   * **Kubernetes** → **Services** for Kubernetes deployments, or
   * **Docker** → **Services** for Docker deployments.
2. On the **Services** page, select the Service name in the **Name** column.
3. Click the **Load Balancers** tab.
4. Click **Configure Load Balancer**. The **Add Load Balancer Listener** pane appears.<br>

   <div align="left"><figure><img src="https://2471407984-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F68cb0s9ce5UIUKWPuYs8%2Fuploads%2FpSlEWrMASUDIFI8itIDm%2FScreenshot%20(334).png?alt=media&#x26;token=9058d08b-b0ef-4c6e-b3be-dc3b38e6b93d" alt="" width="305"><figcaption><p>The <strong>Add Load Balancer Listener</strong> pane</p></figcaption></figure></div>
5. Fill out the required fields based on your configuration needs.
6. Click **Add** to create the Load Balancer.

## Configuring a Load Balancer using rules

Rules define specific configurations for different types of Load Balancers.

For an example of how to configure Load Balancers using rules, see the [Ingress](https://docs.duplocloud.com/docs/automation-platform/kubernetes-overview/ingress-loadbalancer/aks-ingress) use case.

## Restricting Open Access to Public Load Balancers

Restrict open access to your public Load Balancers by enforcing controlled access policies.

1. From the DuploCloud Portal, navigate to **Administrator** -> **System Settings**.
2. Select the **System Config** tab and click **Add**. The **Add Config** pane displays.

<div align="left"><figure><img src="https://2471407984-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2F68cb0s9ce5UIUKWPuYs8%2Fuploads%2FQs3ReNWAfmJYHKJLHaW7%2FLB%20flag.png?alt=media&#x26;token=e3b4e6a6-09fc-4387-8ead-87b7fd790aa0" alt="" width="364"><figcaption><p>The <strong>Add Config</strong> pane in the DuploCloud Portal</p></figcaption></figure></div>

3. From the **Config Type** list box, select **Flags**.
4. From the **Key** list box, select **Deny Open Access To Public LB**.
5. In the **Value** list box, select **True**.
6. Click **Submit**. Open access to public Load Balancers is restricted.