DNS Registration
DNS registration is enabled in one of two ways, depending on how Always On VPN client devices are managed.
Intune
When using the native Microsoft Intune UI to manage Always On VPN profiles, DNS registration can be configured by selecting Enabled next to Register IP addresses with internal DNS in the Base VPN settings section.
ProfileXML
When using custom ProfileXML with PowerShell, SCCM, or Intune, the administrator will define the RegisterDNS element to enable DNS registration.
Known Issues
Some users have reported unexpected behavior when DNS registration is enabled. Specifically, under some circumstances the VPN client will register the IP address of the VPN network interface along with the IP address of its public network interface (Wi-Fi, Ethernet, etc.). However, the VPN client can only be managed using the VPN interface. If the VPN client’s hostname resolves to its public IP address, manage out will fail.
This appears to happen only when Name Resolution Policy Table (NRPT) rules are defined in Intune DNS settings, or if the DomainNameInformation element is defined in ProfileXML.
Resolution
Microsoft recently released fixes for this DNS registration issue for Windows 10. The fix for this issue is included in the following updates.
Windows 10 1803 – KB4507466
Windows 10 1809 – KB4505658
Windows 10 1903 – KB4505903
Additional Configuration
After installing the update, the following registry entry must be defined on each VPN client.
HKLM\SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\DisableNRPTForAdapterRegistration DWORD = 1
To enable this setting, open an elevated PowerShell window and run the following command.
New-ItemProperty -Path ‘HKLM:SYSTEM\CurrentControlSet\Services\Dnscache\Parameters\’ -Name DisableNRPTForAdapterRegistration -PropertyType DWORD -Value 1 -Force
Once complete, restart the client device for the changes to take effect. After validation testing is complete, the registry entry can be deployed to Always On VPN clients using Active Directory group policy preferences or Intune.
Additional Information
Deploying Windows 10 Always On VPN with Intune using Custom ProfileXML
Windows 10 Always On VPN Updates to Improve Connection Reliability
Windows 10 Always On VPN Device Tunnel Configuration using Microsoft Intune