All posts tagged scripts

Always On VPN PowerShell Script Issues in Windows 11

Many administrators are now beginning to test Always On VPN functionality on the latest Microsoft Windows client operating system, Windows 11. Initially, Microsoft had some issues with provisioning and managing Always On VPN profiles on Windows 11 using Microsoft Endpoint Manager/Intune, but those have been resolved. However, some lingering problems may delay enterprise deployments of Always On VPN on Windows 11 for some organizations, specifically those using PowerShell with Active Directory group policy startup scripts or System Center Configuration Manager (SCCM).

Important Note: The issues outlined in this article have been resolved! The fix for the WMI enumeration bug is addressed in the following updates:

Windows 11 21H2 – KB5022905 (build 22000.1641)

Windows 11 22H2 – KB5026446 (build 22621.1778)

MakeProfile.ps1

Microsoft has published guidance for deploying Always On VPN profiles using PowerShell with their MakeProfile.ps1 script. This script extracts configuration details from a template VPN profile to create another PowerShell script called VPN_Profile.ps1, which is used to create the Always On VPN profile. SCCM administrators commonly use VPN_Proifle.ps1 to deploy Always On VPN profiles. However, running this script on Windows 11 fails and returns the following error message.

“Unable to create [VPN profile name] profile: A general error occurred that is not covered by a more specific code.”

This issue appears to be related to a problem with the WMI-to-CSP bridge, specifically enumerating the MDM_VPNv2_01 class in the root\cimv2\mdm\dmmap namespace. Here you can see the template VPN profile with PowerShell and Get-VpnConnection.

However, attempts to view the MDM_VPNv2_01 class of this VPN profile using PowerShell and Get-CimInstance fail.

New-AovpnConnection.ps1

Interestingly, administrators may find that my Always On VPN PowerShell deployment script works more reliably on Windows 11, although not always. In my experience, I’ve found that it sometimes fails once (profile is loaded, but the configuration is incomplete), then works after deleting the profile and creating it again. If the Microsoft-provided script isn’t working, give mine a try and see if it works better for you.

Note: When deploying Always On VPN profiles using my PowerShell deployment script via Active Directory startup scripts, it seems to fail consistently for some reason. Go figure. 😉

Remove-AovpnConnection.ps1

The issues described previously with Windows 11 are also negatively affecting some of my other PowerShell scripts. For example, running Remove-Aovpnconnection.ps1 on Windows 11 fails and returns the following error message.

“A general error occurred that is not covered by a more specific error code.”

Current Status

Microsoft is currently aware of this issue. However, I am aware of no timeframe for resolution at the time of this writing. Hopefully, Microsoft addresses this soon so organizations can move forward with their Windows 11 migration projects.

Additional Information

Microsoft Windows Always On VPN Windows 11 Issues with Microsoft Endpoint Manager/Intune

Microsoft Windows Always On VPN Profile Deployment Script

Microsoft Windows Always On VPN Remove Always On VPN Profile Script

Always On VPN PowerShell Script Repository on GitHub

70 Comments
by Richard M. Hicks on February 7, 2022  •  Permalink
Posted in administration, Always On VPN, AOVPN, Deployment, Device Management, device tunnel, Endpoint Manager, enterprise mobility, GitHub, InTune, MDM, MEM, MEMCM, Microsoft Endpoint Manager, Microsoft Intune, Mobile Device Management, Mobility, Operational Support, PowerShell, ProfileXML, Remote Access, SCCM, System Center Configuration Manager, systems management, troubleshooting, Uncategorized, user tunnel, VPN, Windows 11, XML
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Posted by Richard M. Hicks on February 7, 2022

https://directaccess.richardhicks.com/2022/02/07/always-on-vpn-powershell-script-issues-in-windows-11/

Always On VPN and Intune Proactive Remediation

Always On VPN and Autopilot Hybrid Azure AD Join

When configuring and deploying Windows Always On VPN using Microsoft Endpoint Manager (MEM)/Intune, administrators may find that some settings are not exposed in the MEM UI. In some cases, deploying the configuration profile using custom XML is the workaround. However, many crucial Always On VPN settings are not exposed using either method. Here, administrators must resort to editing settings in the VPN configuration file on the client after provisioning the VPN profile.

Phonebook

A file called rasphone.pbk stores all Windows VPN settings on the endpoint. It includes name/value pairs that correspond to many settings administrators change manually in the GUI. Other settings can be changed using PowerShell. Depending on the connection type, the file can be found in one of two locations.

  • User Tunnel: $env:AppData\Microsoft\Network\Connections\Pbk\rasphone.pbk
  • Device Tunnel: $env:ProgramData\Microsoft\Network\Connections\Pbk\rasphone.pbk

Documentation for Windows VPN client phonebook entry settings can be found here.

Limitations

Unfortunately, editing the rasphone.pbk file isn’t always convenient. Making the changes is technically easy. Administrators can write a simple PowerShell script to update the text file as required. However, automating this at scale is challenging. Thankfully, Intune Proactive Remediations can help.

Proactive Remediations

With Intune Proactive Remediations, administrators can create and deploy script packages to monitor and optionally update specific configuration settings. The package includes two scripts, a detection script, and a remediation script. The detection script looks at the current value of a particular setting and reports on its compliance. The remediation script is triggered to update the setting if the value is incorrect.

Requirements

Intune Proactive Remediations has some specific licensing requirements. Administrators must also enroll devices into Endpoint analytics and provision a Windows Health Monitoring configuration profile. There are also limitations on the size and type of scripts that administrators can use. More information on prerequisites can be found here.

Script Packages

Administrators can create detection and remediation PowerShell scripts to update settings in rasphone.pbk, or optionally, they can download sample scripts from my GitHub repository here. This repository contains user and device tunnel detection and remediation scripts for many popular settings in rasphone.pbk. Examples include updating the VPN Strategy, changing VPN interface metrics, disabling class-based default routes, and many more.

Note: The scripts in my GitHub repository are examples only. While they can be used in production environments, they are basic and may not work as expected in all scenarios. For example, the scripts as written today assume only a single VPN profile provisioned. Unexpected results may occur if more than one VPN profile exists. Please use them at your own risk.

Deployment

In this example, we’ll deploy a Proactive Remediation to disable IKE mobility for user tunnel VPN connections. To configure an Intune Proactive Remediation, open the Microsoft Endpoint Manager portal (https://intune.microsoft.com/) and navigate to Devices > Remediations. After creating or downloading the detection and remediation scripts, perform the following steps to create and deploy a Proactive Remediation script package.

  1. Click Create script package.
  2. Enter a name for the package in the Name field.
  3. Enter a description for the package in the Description field (optional).
  4. Click Next.
  5. Click the blue folder icon next to the Detection script file field and upload the detection script.
  6. Click the blue folder icon next to the Remediation script file field and upload the associated remediation script.
  7. For user tunnel connections, click Yes next to Run this script using the logged-on credentials. For device tunnel connections, click No.
  8. Click Next.
  9. Define scope tags as required.
  10. Click Next.
  11. Assign a group and choose a schedule. The detection script can be run once, daily, hourly, or on an hourly interval.
  12. Click Next, then click Create.

Click Refresh to update the UI to display the newly created script package.

Caveats

Be advised that timing issues could lead to delays in functionality. For example, if there’s a change to an Always On VPN profile after a Proactive Remediation detection script runs, the changes will not be detected until the detection script runs again. Also, changes made while the VPN is active will not take effect until after restarting the connection.

Special Thanks

Special thanks to Tom Klaver at Inspark for turning me on to this feature. It has been an absolute lifesaver for sure!

Additional Information

Microsoft Intune Proactive Remediation Tutorial

Windows VPN Phonebook Entry Settings

Intune Proactive Remediation Script Samples on GitHub

Microsoft Windows Always On VPN Class-Based Default Route and Intune

Microsoft Windows Always On VPN Short Name Access Failure

7 Comments
by Richard M. Hicks on December 6, 2021  •  Permalink
Posted in administration, Always On VPN, AOVPN, Azure, Azure AD, Azure VPN, Azure VPN Gateway, cloud, Endpoint Manager, Enterprise, enterprise mobility, GitHub, InTune, MEM, MEMCM, Microsoft Endpoint Manager, Microsoft Intune, Mobility, Operational Support, PowerShell, public cloud, Remote Access, SCCM, System Center Configuration Manager, systems management, troubleshooting, user tunnel, VPN, Windows 10, Windows 11
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Posted by Richard M. Hicks on December 6, 2021

https://directaccess.richardhicks.com/2021/12/06/always-on-vpn-and-intune-proactive-remediation/

DirectAccess Troubleshooting with Nmap

DirectAccess IP-HTTPS Discovery Script for NmapDirectAccess troubleshooting can be made much easier using open source tools such as Nmap. Nmap can be used to perform many essential network connectivity and configuration checks, including validating network paths, confirming DirectAccess server response, and viewing SSL configuration. Nmap can also be used to ensure that the attack surface of the DirectAccess server is properly minimized. Some tests can be performed using only native Nmap functionality, while others require the use of specialized Nmap scripts that are included with the tool.

Installation

Nmap can be installed on a wide variety of operating systems, including Windows. If you plan to install Nmap on Windows, be sure to also install WinPcap and the Microsoft Visual C++ 2013 Redistributable. The Visual C++ component is included with the Nmap download. WinPcap must be downloaded separately here.

Testing External Connectivity

Validating external connectivity is often one of the first DirectAccess troubleshooting steps I take. Confirm that the DirectAccess public hostname resolves to the correct IP address, then run the following Nmap command to validate network connectivity from the Internet to the DirectAccess server.

nmap -n -Pn -p443 <da_public_hostname>

DirectAccess Troubleshooting with Nmap

If the hostname resolves correctly and the network path is complete, the server should respond and Nmap will show the port as open. However, this doesn’t necessarily mean that the DirectAccess server is the device that replied! Due to misconfiguration, it is possible that another server or network device listening on TCP port 443 responded, so this is not a conclusive test.

DirectAccess Server Response

To confirm the DirectAccess server is responding to HTTPS requests and not some other server or device, run the following Nmap command with the ip-https-discover script.

nmap -n -Pn -p443 <da_public_hostname> –script ip-https-discover

If the DirectAccess server responds to the request, Nmap will return the following message:

IP-HTTPS is supported. This indicates that this host supports Microsoft DirectAccess.

DirectAccess Troubleshooting with Nmap

If the port is open but the script does not return this message, it is likely that another server or device is responding on TCP port 443, not the DirectAccess server.

Note: If an Application Delivery Controller (ADC) is configured to perform IP-HTTPS preauthentication, the Nmap IP-HTTPS discovery script will not return this result. This is expected and by design.

SSL Certificate Validation

It is not uncommon for DirectAccess clients to fail to connect via IP-HTTPS because of SSL certificate issues. Specifically, an SSL certificate that is not trusted, is expired, or its subject field does not match the public hostname will prevent DirectAccess clients from connecting. To view the SSL certificate configuration of a DirectAccess server, run the following Nmap command with the ssl-cert script.

nmap -n -Pn -p443 <da_public_hostname> –script ssl-cert

DirectAccess Troubleshooting with Nmap

SSL Cipher Suite Configuration

Occasionally there can be issues with the SSL configuration on the DirectAccess server that prevent some clients from connecting, or result in poor performance. This commonly occurs when administrators perform SSL hardening on the DirectAccess server and remove support for null cipher suites. Null cipher suites should never be disabled on the DirectAccess server. They are important to ensure the highest levels of performance for Windows 8.x and Windows 10 clients. Also, if an Application Delivery Controller (ADC) or load balancer is performing SSL offload, lack of support for null cipher suites will prevent Windows 8.x and Windows 10 clients from connecting. To determine if the DirectAccess server supports null cipher suites, run the following Nmap command with the ssl-enum-ciphers script.

nmap -n -Pn -p443 <da_public_hostname> –script ssl-enum-ciphers

DirectAccess Troubleshooting with Nmap

Attack Surface Audit

If DirectAccess implementation and security best practices are followed, the DirectAccess server will be behind an edge firewall. The only port required to be allowed inbound for DirectAccess is TCP port 443. It is recommended that a full port scan be performed against the DirectAccess server’s public IPv4 address to identify any unnecessary ports that may be open externally. To perform a full port scan, run the following Nmap command.

nmap -n -Pn -p- <da_public_hostname>

Ideally it should look like this.

DirectAccess Troubleshooting with Nmap

If it looks something like this, you’re in serious trouble!

DirectAccess Troubleshooting with Nmap

The DirectAccess server should never be listening for requests other that HTTPS on the public Internet. Exposing services such as SMB (TCP port 445), RDP (TCP port 3389), and others presents a significant security risk. It is recommended that edge firewalls be configured to allow inbound TCP port 443 only. If the DirectAccess server is connected directly to the public Internet (not recommended!) then the Windows Firewall should be configured to restrict access to inbound TCP port 443 only.

Additional Resources

DirectAccess IP-HTTPS Discovery Script for Nmap
Planning and Implementing DirectAccess with Windows Server 2016 on Pluralsight
Implementing DirectAccess with Windows Server 2016 Book
DirectAccess Troubleshooting and Consulting Services

3 Comments
by Richard M. Hicks on April 20, 2017  •  Permalink
Posted in DirectAccess, IP-HTTPS, IPv6 Transition, nmap, Remote Access, Security, SSL and TLS, troubleshooting, Windows 10, Windows 7, Windows 8, Windows 8.1, Windows Server 2012 R2, Windows Server 2016
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Posted by Richard M. Hicks on April 20, 2017

https://directaccess.richardhicks.com/2017/04/20/directaccess-troubleshooting-with-nmap/