---
title: "Configuring IIS as an HTTPS Reverse Proxy for OPC"
slug: "windows-iis-reverse-proxy-setup"
updated: 2025-05-20T06:59:18Z
published: 2025-05-20T06:59:18Z
canonical: "help.scalefusion.com/windows-iis-reverse-proxy-setup"
---

> ## Documentation Index
> Fetch the complete documentation index at: https://help.scalefusion.com/llms.txt
> Use this file to discover all available pages before exploring further.

# Configuring IIS as an HTTPS Reverse Proxy for OPC

In a Windows environment, Internet Information Services (IIS) can be configured to act as a reverse proxy. This allows IIS to handle incoming requests from clients and forward them to backend servers. Essentially, IIS acts as a gateway, hiding the internal server structure and improving security and performance.

This guide outlines the steps to configure Internet Information Services (IIS) on a Windows Server to act as an HTTPS reverse proxy for your OPC (On-Premise Connector) server. This setup enables secure, encrypted communication between clients and the OPC server, which is crucial for protecting sensitive industrial data.

## **Pre-requisites**

1. A Windows Server with IIS installed.
2. URL Rewrite module for IIS.
3. Application Request Routing (ARR) module for IIS.
4. An SSL certificate in .pfx format (without a password).
5. The Fully Qualified Domain Name (FQDN) that will be used for OPC in your MDM dashboard (e.g., opc.yourdomain.com).

## **Step 1: Install Required IIS Modules**

1. **Install URL Rewrite:**

- Download the URL Rewrite module from: [https://download.microsoft.com/download/1/2/8/128E2E22-C1B9-44A4-BE2A-5859ED1D4592/rewrite_amd64_en-US.msi](https://download.microsoft.com/download/1/2/8/128E2E22-C1B9-44A4-BE2A-5859ED1D4592/rewrite_amd64_en-US.msi)
- Run the downloaded MSI installer.

1. **Install Application Request Routing (ARR):**

- Download the Application Request Routing module from: [https://download.microsoft.com/download/e/9/8/e9849d6a-020e-47e4-9fd0-a023e99b54eb/requestRouter_amd64.msi](https://download.microsoft.com/download/e/9/8/e9849d6a-020e-47e4-9fd0-a023e99b54eb/requestRouter_amd64.msi)
- Run the downloaded MSI installer.

## **Step 2: Open IIS Manager**

1. Click on the Windows search bar.
2. Type **IIS**.
3. Double-click on **Internet Information Services (IIS) Manager** to open it.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-NZMI9ZXH.png)

## **Step 3: Import the SSL Certificate**

1. In IIS Manager, in the **Connections** pane on the left, select the server name.
2. Double-click on **Server Certificates** in the center pane.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-1XI1SSYT.png)
3. In the **Actions** pane on the right, click on **Import...**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-PTKVT8QX.png)
4. In the Import Certificate dialog box:

- Browse to the location of your .pfx certificate file.
- Enter the certificate password (if you set one). **Important:** It is strongly recommended to use a password for your SSL certificate. If you followed best practices, you will have a password.
- Check **Allow this certificate to be exported** if needed.
- Click **OK**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-AU2WG416.png)

## **Step 4: Configure Application Request Routing (ARR)**

1. In IIS Manager, in the **Connections** pane, select the server name.
2. Double-click on **Application Request Routing Cache** in the center pane.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-NCB6VE7S.png)
3. In the **Actions** pane on the right, click on **Server Proxy Settings...**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-HN2YCX2Y.png)
4. In the Server Proxy Settings dialog box:

- Check the **Enable Proxy** checkbox.
- Click **Apply** in the **Actions** pane

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-Y15HYQK1.png)

## **Step 5: Add a Website for the Reverse Proxy**

1. In IIS Manager, in the **Connections** pane, expand the server name and click on **Sites**.
2. Click on **Add Website...** under Actions.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-07C3L9I6.png)
3. In the Add Website dialog box:

- **Site name:** Enter a descriptive name for the website (e.g., OPC Reverse Proxy).
- **Physical path:** Create a new, empty folder (e.g., C:\OPCProxy) and enter its path. This folder will not contain your actual web content, but IIS requires a path.
- **Hostname:** Enter the FQDN that you will use for OPC in your MDM dashboard (e.g., opc.yourdomain.com).
- Click **OK**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-B3K1IBCE.png)

## **Step 6: Configure Website Bindings**

1. In IIS Manager, in the **Connections** pane, expand **Sites** and select the website you just created.
2. In the **Actions** pane on the right, click on **Bindings...**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-UXRS45KE.png)
3. In the Site Bindings dialog box, click on **Add...**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-8OQC11UN.png)
4. In the Add Site Binding dialog box:

- **Type:** Select **https**.
- **Hostname:** Enter the FQDN you will use for OPC (e.g., opc.yourdomain.com).
- **SSL certificate:** Click on the **Select...** button and choose the SSL certificate you imported in Step 3.
- Click **OK** in the Add Site Binding dialog box.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-2S1EVASR.png)

1. Click **Close** in the Site Bindings dialog box.

## **Step 7: Configure URL Rewrite Rules**

1. In IIS Manager, in the **Connections** pane, expand **Sites** and select the website you created.
2. Double-click on **URL Rewrite** in the center pane.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-BZ3BL4M4.png)
3. If there are any existing rules in the **Inbound Rules** or **Outbound Rules** sections, you may need to remove or modify them depending on your specific requirements.
4. In the **Actions** pane on the right, click on **Add Rule(s)...**.
5. In the Add Rules dialog box, double-click on **Reverse Proxy**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-1D0HI1LB.png)
6. In the **Add Rewrite Rules** dialog box:

- Enter the server name or IP address and port of your OPC server (e.g., http://127.0.0.1:28767).
- Ensure that the **Enable SSL Offloading** checkbox is checked if your OPC server is on the same machine and does not require HTTPS. If your OPC server *does* require HTTPS, leave this unchecked and ensure your OPC server is configured correctly.
- Click **OK**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-EOKE83S0.png)

## **Step 8: Restart the Website**

1. In IIS Manager, in the **Connections** pane, select the website you configured.
2. In the **Actions** pane on the right, click on **Restart**.

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-IMB0DO36.png)

## **Step 9: Verify the Configuration**

1. Open a web browser and navigate to a URL that should be routed to your OPC server (e.g., https://opc.yourdomain.com/opc/heart-beat/pass). Replace opc.yourdomain.com with your actual FQDN.
2. If the configuration is correct, you should see the expected output from your OPC server. For example, you might see a response like:

![](https://cdn.document360.io/175c0eac-012f-4410-bdc5-ac60794f82d8/Images/Documentation/image-Q0L8HB4Z.png)

If you see the correct output, you have successfully configured IIS as an HTTPS reverse proxy for your OPC server.