Always On VPN RADIUS Configuration Missing

Windows Server Routing and Remote Access Service (RRAS) is a popular choice for administrators deploying Always On VPN. It is easy to configure and scales out easily. Most commonly, RRAS servers are configured to use RADIUS authentication to provide user authentication for Always On VPN client connections. The RADIUS server can be Microsoft Network Policy and Access Server (NPAS, or simply NPS) or a third-party RADIUS solution. It is best to have the RADIUS service running on a server separate from the RRAS server.

RADIUS Authentication

Administrators can configure RADIUS authentication by opening the Routing and Remote Access management console (rrasmgmt.msc), right-clicking the VPN server, then choosing Properties > Security. Click the Configure button to configure authentication and accounting providers accordingly.

RADIUS Options Missing

In some cases, the administrator will notice that the option to configure RADIUS authentication and accounting servers is missing. In its place is the following error message.

“Because Network Policy Server (NPS) is installed, you must use it to configure authentication and accounting providers. To configure authentication and accounting providers, create or modify connection request policies.”

Configuration Options

It might be tempting for administrators to follow this guidance when presented with this message by opening the Network Policy management console (nps.msc) to configure it. However, that is not recommended or necessary. This message results from a common configuration error that should be corrected.

NPS Role Installed

The error message above occurs when an administrator mistakenly installs the NPAS role on the RRAS server itself. Again, this is not recommended or required. To resolve this issue, uninstall the NPS role by opening an elevated PowerShell command window and running the following command.

Uninstall-WindowsFeature NPAS

Configuration Corrupted

After removing the NPAS role from the RRAS server, administrators may encounter the following error message when configuring RADIUS authentication and accounting servers in RRAS.

“The connection request policy used for authentication and accounting configuration is corrupted. Either install Network Policy Server (NPS) and restore the connection request policy manually, or click Repair Settings to restore the connection request policy by using Windows Accounting and Windows Authentication.”

Repair Settings

To resolve this issue, click the Repair Settings button. Once complete, RADIUS authentication and accounting configuration should work as expected.

Additional Information

Always On VPN Network Policy Server (NPS) Auditing and Logging

Always On VPN Network Policy Server (NPS) Load Balancing

Always On VPN and Windows Server 2019 Network Policy Server (NPS) Bug

Always On VPN NPS Auditing and Logging

The Network Policy Server (NPS) event log is incredibly valuable for administrators when troubleshooting Always On VPN user tunnel connectivity issues. Administrators can find these pertinent events by opening the Event Viewer on the NPS server (eventvwr.msc) and navigating to Custom Views > Server Roles > Network Policy and Access Services.

Event Logs

When configured correctly, event logs will record the disposition of all authentication requests, allowed or denied. The two most common recorded events are event IDs 6272 (access granted) and 6273 (access denied).

NPS Event ID 6272 – Access granted.

NPS Event ID 6273 – Access denied.

Auditing

In some cases, administrators may find none of these events recorded even though user authentication is working correctly. Here, the only events recorded are NPS informational events indicating which domain controller the NPS server is using to perform authentication.

The lack of 6272 and 6273 events in the event log indicates that auditing for NPS events is not enabled. Open an elevated PowerShell window and run the following command to view the current auditing setting for NPS events.

auditpol.exe /get /subcategory:”Network Policy Server”

Open an elevated PowerShell window and run the following command to enable auditing for NPS events.

auditpol.exe /set /subcategory:”Network Policy Server” /success:enable /failure:enable

Group Policy

Alternatively, consider using Active Directory group policy to enforce the NPS server auditing settings. Open the Group Policy Management Console (GPMC) and create a new GPO. Next, navigate to Computer Configuration > Policies > Windows Settings > Security Settings > Advanced Audit Policy Configuration > Audit Policies > Logon/Logoff > Audit Network Policy Server and select the option to audit both success and failure attempts.

Once complete, link this GPO to the OU where the NPS servers reside.

Missing Events

If auditing is enabled and there are no recorded 6272 or 6273 events, the NPS server did not receive any authentication requests from the VPN server. Review the event logs on any other NPS servers if there is more than one configured. In addition, this may indicate that network communication between the VPN and NPS server is blocked. Ensure network connectivity and name resolution are working as expected.

Troubleshooting Guides

Are you interested in learning more about Always On VPN troubleshooting? My Always On VPN book contains an entire chapter dedicated to troubleshooting. Also, my Always On VPN video training course on Pluralsight includes a module on troubleshooting. The video training course is available to Pluralsight subscribers only. If you don’t have a Pluralsight subscription, you can sign up for a free trial here.

Additional Information

Troubleshooting Always On VPN Errors 691 and 812

Troubleshooting Always On VPN Errors 691 and 812 – Part 2

Troubleshooting Always On VPN Errors 691 and 812 – Part 3

Always On VPN NPS Load Balancing

Always On VPN Book Available for Pre-Order

Great news! My new book, Implementing Always On VPN, is now available for pre-order on Amazon.com. This new book, scheduled for release in late 2021, is a comprehensive implementation guide for Windows 10 Always On VPN. Drawing on many years of experience deploying Always On VPN for organizations worldwide, it covers all aspects of an Always On VPN deployment, including planning and design, prerequisite gathering, infrastructure preparation, and client deployment.

In addition, it contains detailed, prescriptive guidance for advanced configuration options such as application and traffic filtering and proxy server configuration. Cloud deployments using Azure VPN gateway and Virtual WAN are covered, and it includes guidance for configuring Azure MFA and Conditional Access.

Also, the book includes thorough guidance for provisioning certificates using Microsoft Endpoint Manager/Intune using both PKCS and SCEP. It outlines options for high availability for VPN and authentication infrastructure and provides details for ongoing system maintenance and operational support.

Finally, the book has an entire chapter dedicated to troubleshooting and resolving common (and not so common!) issues encountered with Windows 10 Always On VPN.

Reserve your copy today. Pre-order Implementing Always On VPN now!

Chapter List

  1. Always On VPN Overview
  2. Plan an Always On VPN Deployment
  3. Prepare the Infrastructure
  4. Configure Windows Server for Always On VPN
  5. Provision Always On VPN clients
  6. Advanced Configuration
  7. Cloud Deployments
  8. Deploy Certificates with Intune
  9. Integrating Azure MFA
  10. High Availability
  11. Monitor and Report
  12. Troubleshooting
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