Tutorial: Add an on-premises application for remote access through Application Proxy in Azure Active Directory

Azure Active Directory (Azure AD) has an Application Proxy service that enables users to access on-premises applications by signing in with their Azure AD account. This tutorial prepares your environment for use with Application Proxy. Once your environment is ready, you'll use the Azure portal to add an on-premises application to your Azure AD tenant.

This tutorial:

  • Opens ports for outbound traffic and allows access to specific URLs
  • Installs the connector on your Windows server, and registers it with Application Proxy
  • Verifies the connector installed and registered correctly
  • Adds an on-premises application to your Azure AD tenant
  • Verifies a test user can sign on to the application by using an Azure AD account

Before you begin

To add an on-premises application to Azure AD, you need:

  • A Microsoft Azure AD premium subscription
  • An application administrator account
  • User identities must be synchronized from an on-premises directory or created directly within your Azure AD tenants. Identity synchronization allows Azure AD to pre-authenticate users before granting them access to App Proxy published applications and to have the necessary user identifier information to perform single sign-on (SSO).

Windows server

To use Application Proxy, you need a Windows server running Windows Server 2012 R2 or later. You'll install the Application Proxy connector on the server. This connector server needs to connect to the Application Proxy services in Azure, and the on-premises applications that you plan to publish.

For high availability in your production environment, we recommend having more than one Windows server. For this tutorial, one Windows server is sufficient.

Important

If you are installing the connector on Windows Server 2019 there is a HTTP2 limitation. A workaround to use the connector on this version is adding the following registry key and restarting the server. Note, this is a machine registry wide key. HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\Windows\CurrentVersion\Internet Settings\WinHttp\EnableDefaultHttp2 (DWORD) Value: 0

Recommendations for the connector server

  1. Physically locate the connector server close to the application servers to optimize performance between the connector and the application. For more information, see Network topology considerations.
  2. The connector server and the web applications servers should belong to the same Active Directory domain or span trusting domains. Having the servers in the same domain or trusting domains is a requirement for using single sign-on (SSO) with Integrated Windows Authentication (IWA) and Kerberos Constrained Delegation (KCD). If the connector server and web application servers are in different Active Directory domains, you need to use resource-based delegation for single sign-on. For more information, see KCD for single sign-on with Application Proxy.

Warning

If you've deployed Azure AD Password Protection Proxy, do not install Azure AD Application Proxy and Azure AD Password Protection Proxy together on the same machine. Azure AD Application Proxy and Azure AD Password Protection Proxy install different versions of the Azure AD Connect Agent Updater service. These different versions are incompatible when installed together on the same machine.

TLS requirements

The Windows connector server needs to have TLS 1.2 enabled before you install the Application Proxy connector.

To enable TLS 1.2:

  1. Set the following registry keys:

    [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2]
    [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Client] "DisabledByDefault"=dword:00000000 "Enabled"=dword:00000001
    [HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Control\SecurityProviders\SCHANNEL\Protocols\TLS 1.2\Server] "DisabledByDefault"=dword:00000000 "Enabled"=dword:00000001
    [HKEY_LOCAL_MACHINE\SOFTWARE\Microsoft\.NETFramework\v4.0.30319] "SchUseStrongCrypto"=dword:00000001
    
  2. Restart the server.

Important

To provide the best-in-class encryption to our customers, the Application Proxy service limits access to only TLS 1.2 protocols. These changes were gradually rolled out and effective since August 31, 2019. Make sure that all your client-server and browser-server combinations are updated to use TLS 1.2 to maintain connection to Application Proxy service. These include clients your users are using to access applications published through Application Proxy. See Preparing for TLS 1.2 in Office 365 for useful references and resources.

Prepare your on-premises environment

Start by enabling communication to Azure data centers to prepare your environment for Azure AD Application Proxy. If there's a firewall in the path, make sure it's open. An open firewall allows the connector to make HTTPS (TCP) requests to the Application Proxy.

Open ports

Open the following ports to outbound traffic.

Port number How it's used
80 Downloading certificate revocation lists (CRLs) while validating the SSL certificate
443 All outbound communication with the Application Proxy service

If your firewall enforces traffic according to originating users, also open ports 80 and 443 for traffic from Windows services that run as a Network Service.

Allow access to URLs

Allow access to the following URLs:

URL How it's used
*.msappproxy.net
*.servicebus.windows.net
Communication between the connector and the Application Proxy cloud service
mscrl.microsoft.com:80
crl.microsoft.com:80
ocsp.msocsp.com:80
www.microsoft.com:80
Azure uses these URLs to verify certificates.
login.windows.net
secure.aadcdn.microsoftonline-p.com
*.microsoftonline.com
*.microsoftonline-p.com
*.msauth.net
*.msauthimages.net
*.msecnd.net
*.msftauth.net
*.msftauthimages.net
*.phonefactor.net
enterpriseregistration.windows.net
management.azure.com
policykeyservice.dc.ad.msft.net
The connector uses these URLs during the registration process.

You can allow connections to *.msappproxy.net and *.servicebus.windows.net if your firewall or proxy lets you configure DNS allow lists. If not, you need to allow access to the Azure IP ranges and Service Tags - Public Cloud. The IP ranges are updated each week.

Install and register a connector

To use Application Proxy, install a connector on each Windows server you're using with the Application Proxy service. The connector is an agent that manages the outbound connection from the on-premises application servers to Application Proxy in Azure AD. You can install a connector on servers that also have other authentication agents installed such as Azure AD Connect.

To install the connector:

  1. Sign in to the Azure portal as an application administrator of the directory that uses Application Proxy. For example, if the tenant domain is contoso.com, the admin should be admin@contoso.com or any other admin alias on that domain.

  2. Select your username in the upper-right corner. Verify you're signed in to a directory that uses Application Proxy. If you need to change directories, select Switch directory and choose a directory that uses Application Proxy.

  3. In left navigation panel, select Azure Active Directory.

  4. Under Manage, select Application proxy.

  5. Select Download connector service.

    Download connector service to see the Terms of Service

  6. Read the Terms of Service. When you're ready, select Accept terms & Download.

  7. At the bottom of the window, select Run to install the connector. An install wizard opens.

  8. Follow the instructions in the wizard to install the service. When you're prompted to register the connector with the Application Proxy for your Azure AD tenant, provide your application administrator credentials.

    • For Internet Explorer (IE), if IE Enhanced Security Configuration is set to On, you may not see the registration screen. To get access, follow the instructions in the error message. Make sure that Internet Explorer Enhanced Security Configuration is set to Off.

General remarks

If you've previously installed a connector, reinstall to get the latest version. To see information about previously released versions and what changes they include, see Application Proxy: Version Release History.

If you choose to have more than one Windows server for your on-premises applications, you'll need to install and register the connector on each server. You can organize the connectors into connector groups. For more information, see Connector groups.

If your organization uses proxy servers to connect to the internet, you need to configure them for Application Proxy. For more information, see Work with existing on-premises proxy servers.

For information about connectors, capacity planning, and how they stay up-to-date, see Understand Azure AD Application Proxy connectors.

Verify the connector installed and registered correctly

You can use the Azure portal or your Windows server to confirm that a new connector installed correctly.

Verify the installation through Azure portal

To confirm the connector installed and registered correctly:

  1. Sign in to your tenant directory in the Azure portal.

  2. In the left navigation panel, select Azure Active Directory, and then select Application Proxy under the Manage section. All of your connectors and connector groups appear on this page.

  3. View a connector to verify its details. The connectors should be expanded by default. If the connector you want to view isn't expanded, expand the connector to view the details. An active green label indicates that your connector can connect to the service. However, even though the label is green, a network issue could still block the connector from receiving messages.

    Azure AD Application Proxy Connectors

For more help with installing a connector, see Problem installing the Application Proxy Connector.

Verify the installation through your Windows server

To confirm the connector installed and registered correctly:

  1. Open the Windows Services Manager by clicking the Windows key and entering services.msc.

  2. Check to see if the status for the following two services is Running.

    • Microsoft AAD Application Proxy Connector enables connectivity.

    • Microsoft AAD Application Proxy Connector Updater is an automated update service. The updater checks for new versions of the connector and updates the connector as needed.

      App Proxy Connector services - screenshot

  3. If the status for the services isn't Running, right-click to select each service and choose Start.

Add an on-premises app to Azure AD

Now that you've prepared your environment and installed a connector, you're ready to add on-premises applications to Azure AD.

  1. Sign in as an administrator in the Azure portal.

  2. In the left navigation panel, select Azure Active Directory.

  3. Select Enterprise applications, and then select New application.

  4. In the On-premises applications section, select Add an on-premises application.

  5. In the Add your own on-premises application section, provide the following information about your application:

    Field Description
    Name The name of the application that will appear on the access panel and in the Azure portal.
    Internal URL The URL for accessing the application from inside your private network. You can provide a specific path on the backend server to publish, while the rest of the server is unpublished. In this way, you can publish different sites on the same server as different apps, and give each one its own name and access rules.

    If you publish a path, make sure that it includes all the necessary images, scripts, and style sheets for your application. For example, if your app is at https://yourapp/app and uses images located at https://yourapp/media, then you should publish https://yourapp/ as the path. This internal URL doesn't have to be the landing page your users see. For more information, see Set a custom home page for published apps.
    External URL The address for users to access the app from outside your network. If you don't want to use the default Application Proxy domain, read about custom domains in Azure AD Application Proxy.
    Pre Authentication How Application Proxy verifies users before giving them access to your application.

    Azure Active Directory - Application Proxy redirects users to sign in with Azure AD, which authenticates their permissions for the directory and application. We recommend keeping this option as the default so that you can take advantage of Azure AD security features like Conditional Access and Multi-Factor Authentication. Azure Active Directory is required for monitoring the application with Microsoft Cloud Application Security.

    Passthrough - Users don't have to authenticate against Azure AD to access the application. You can still set up authentication requirements on the backend.
    Connector Group Connectors process the remote access to your application, and connector groups help you organize connectors and apps by region, network, or purpose. If you don't have any connector groups created yet, your app is assigned to Default.

    If your application uses WebSockets to connect, all connectors in the group must be version 1.5.612.0 or later.
  6. If necessary, configure Additional settings. For most applications, you should keep these settings in their default states.

    Field Description
    Backend Application Timeout Set this value to Long only if your application is slow to authenticate and connect. At default, the backend application timeout has a length of 85 seconds. When set to long, the backend timeout is increased to 180 seconds.
    Use HTTP-Only Cookie Set this value to Yes to have Application Proxy cookies include the HTTPOnly flag in the HTTP response header. If using Remote Desktop Services, set this value to No.
    Use Secure Cookie Set this value to Yes to transmit cookies over a secure channel such as an encrypted HTTPS request.
    Use Persistent Cookie Keep this value set to No. Only use this setting for applications that can't share cookies between processes. For more information about cookie settings, see Cookie settings for accessing on-premises applications in Azure Active Directory.
    Translate URLs in Headers Keep this value as Yes unless your application required the original host header in the authentication request.
    Translate URLs in Application Body Keep this value as No unless you have hardcoded HTML links to other on-premises applications and don't use custom domains. For more information, see Link translation with Application Proxy.

    Set this value to Yes if you plan to monitor this application with Microsoft Cloud App Security (MCAS). For more information, see Configure real-time application access monitoring with Microsoft Cloud App Security and Azure Active Directory.
  7. Select Add.

Test the application

You're ready to test the application is added correctly. In the following steps, you'll add a user account to the application, and try signing in.

Add a user for testing

Before adding a user to the application, verify the user account already has permissions to access the application from inside the corporate network.

To add a test user:

  1. Select Enterprise applications, and then select the application you want to test.
  2. Select Getting started, and then select Assign a user for testing.
  3. Under Users and groups, select Add user.
  4. Under Add assignment, select Users and groups. The User and groups section appears.
  5. Choose the account you want to add.
  6. Choose Select, and then select Assign.

Test the sign-on

To test the sign-on to the application:

  1. In your browser, navigate to the external URL that you configured during the publish step. You should see the start screen.
  2. Sign in as the user you created in the previous section.

For troubleshooting, see Troubleshoot Application Proxy problems and error messages.

Next steps

In this tutorial, you prepared your on-premises environment to work with Application Proxy, and then installed and registered the Application Proxy connector. Next, you added an application to your Azure AD tenant. You verified that a user can sign on to the application by using an Azure AD account.

You did these things:

  • Opened ports for outbound traffic and allowed access to specific URLs
  • Installed the connector on your Windows server, and registered it with Application Proxy
  • Verified the connector installed and registered correctly
  • Added an on-premises application to your Azure AD tenant
  • Verified a test user can sign on to the application by using an Azure AD account

You're ready to configure the application for single sign-on. Use the following link to choose a single sign-on method and to find single sign-on tutorials.