Always On VPN Servers and Failover

When configuring Microsoft Always On VPN, one of the first and most crucial settings is defining the public hostname of the VPN server to which clients connect. If you’re deploying Always On VPN client configuration settings using Intune—either with the native VPN policy template or a custom XML profile—you’ll see that multiple server entries are supported. Intune even allows administrators to define a “default server.” At first glance, this might suggest that the client will try the default server first and automatically fail over to the others if it’s unavailable. Unfortunately, that’s not how it works.

Intune VPN Template

When using the native Intune VPN device configuration template, administrators will find multiple entry fields for the servers in the Base VPN section.

In the example below, the Global VPN entry is marked as ‘default’.

Custom XML

When defining VPN settings using XML configuration, administrators can also list multiple servers.

Interestingly, the VPNv2 CSP used by custom XML profiles doesn’t support the concept of a “default server” at all.

How It Really Works

Defining multiple servers in the Always On VPN profile does not enable automatic failover. The client connects only to the first server in the list. The so-called “default server” setting in Intune is ignored, and the GUI even allows you to mark all servers as default, which is meaningless.

However, the configuration isn’t entirely useless. If you define multiple servers, they’ll appear on the client side as manual options. If the first server becomes unavailable, the user can open the Settings app, navigate to the advanced settings of the Always On VPN profile, and select an alternate server to connect manually.

Summary

Although Intune and XML configurations allow multiple VPN servers, Always On VPN does not provide automatic failover. Clients only attempt to connect to the first server in the list, and the “default server” setting in Intune has no effect. Multiple entries are still useful, but only for manual server selection by end-users when the primary server is down. For true automated high availability and redundancy, consider an external solution such as Azure Traffic Manager.

Additional Information

Always On VPN Multisite with Azure Traffic Manager

Microsoft Intune Learning Resources for Always On VPN Administrators

Note: This post has been updated and republished to reflect the return to the Microsoft Intune product name and to include updated learning resources for Always On VPN administrators.

Microsoft Intune is the recommended solution for deploying and managing Windows Always On VPN client configuration settings. Always On VPN is designed for Mobile Device Management (MDM), with configuration settings deployed specifically to the VPNv2 Configuration Service Provider (CSP) interface.

Resources

Getting up to speed on all things MEM isn’t difficult at all. I’ve found the MEM community to be exceedingly helpful, and there are many available training resources in various formats from which to choose.

Books

The following is a list of Microsoft Endpoint Manager books Always On VPN administrators will find most helpful for learning about MEM.

YouTube

The Intune Training channel on YouTube is an incredibly valuable resource for Always On VPN administrators learning MEM. Hosted by Steven Hosking, Adam Gross, and Ben Reader, there are countless videos covering important MEM configuration tasks.

Pluralsight

Pluralsight offers video training courses for a wide variety of IT-related topics. Recently I published the  Implementing Always On VPN video training course. There are several Microsoft Endpoint Manager video training courses available as well. Pluralsight is available via subscription. You can sign up for a free trial here if you don’t have a subscription.

Conferences

The Midwest Management Summit (MMS) is the premier event for systems management professionals. Their annual conference takes place each spring in the U.S. (Minneapolis, MN). The event is the best place to learn about Microsoft Endpoint Manager and network with systems management professionals worldwide.

ViaMonstra Online Academy

I will be delivering the Mastering Certificates with Microsoft Intune training course at the ViaMonstra online training academy May 14-16, 2024. This three-day live, interactive training course provides a comprehensive deep dive into all aspects of deploying and managing digital certificates using Microsoft Intune. Microsoft Cloud PKI will also be covered. Space is limited, so register today!

Additional Resources

As a reminder, Microsoft Intune topics such as certificate deployment and Always On VPN profile deployment and management are covered in detail in both my Implementing Always On VPN book and the Implementing Always On VPN video training course on Pluralsight. 😁

Always On VPN Disconnects in Windows 11

Always On VPN administrators migrating their endpoints to Windows 11 may encounter a scenario where Always On VPN randomly disconnects when the VPN profile is deployed using Microsoft Intune. The same configuration deployed to Windows 10 devices works reliably, however. In addition, Always On VPN profiles deployed using PowerShell (natively or with SCCM) or Dynamic Profile Configurator (DPC) do not experience this problem.

Troubleshooting

Administrators troubleshooting this issue will find the root cause is associated with the Always On VPN profiles being removed and replaced each time the device syncs with Intune. This occurs even if there are no changes to the configuration. Removing and replacing the Always On VPN profiles on each device sync is unnecessary, of course, but is also highly disruptive to connected users.

Intune and XML

The Intune team identified the issue, and a fix was made available in the August update. However, many of you have reported the issue persists with some Windows 11 clients after installing the latest updates. Further investigation indicates that although the issue has been resolved when using Intune and the native VPN device configuration profile template, the problem still occurs when using the Custom device configuration template.

Workaround

Microsoft is aware of the issues with deploying Always On VPN client configuration settings using XML in Intune, but there’s no indication when or if they will fix it. Until then, administrators have two options to address this problem.

Native VPN Template

When deploying Always On VPN client configuration settings to Windows 11 endpoints, use the native VPN device configuration template, as shown here.

Using the native VPN template does have some limitations, however. The following settings are not exposed using the native VPN template and can only be configured using XML.

XML

If you must use XML, I’ve had some success by ensuring the order and syntax of XML settings is exactly as Intune expects. Follow the steps below to confirm the XML settings order in your XML configuration file.

  1. Deploy your XML file with Intune.
  2. Run Get-VpnClientProfileXML.ps1 to extract the deployed XML settings.
  3. Compare the order of settings to your existing XML.
  4. Compare the syntax of all settings. For example, the <Servers> section should list the server FQDN twice, separated by a semi-colon.
  5. Make changes to ensure all settings in your XML are in the same order as the extracted XML.
  6. Publish a new XML configuration file using Intune and test.

I’ll caution you that this workaround doesn’t always work reliably. Some customers report that this solved their problems entirely, while others have indicated it does not. My testing shows the same results. Let us know in the comments below if this works for you!

Reference XML

I have published an Always On VPN XML configuration file on GitHub for reference. It includes all common settings using the order and syntax required to ensure reliable operation. As a reminder, the sample file includes many settings that aren’t required. It is published as guidance for reference only.

Additional Information

Always On VPN Windows 11 Issues with Intune

Always On VPN PowerShell Script Issues in Windows 11