Top 5 DirectAccess Troubleshooting PowerShell Commands

Top 5 DirectAccess Troubleshooting PowerShell CommandsNative PowerShell commands in Windows 10 make DirectAccess troubleshooting much easier than older operating systems like Windows 7. For example, with one PowerShell command an administrator can quickly determine if a DirectAccess client has received the DirectAccess client settings policy. In addition, PowerShell can be used to view the status of the connection and retrieve additional information or error codes that can be helpful for determining the cause of a failed connection. Further, PowerShell can also be used to review configuration details and perform other troubleshooting and connectivity validation tasks.

Here are my top 5 PowerShell commands for troubleshooting DirectAccess on Windows 10.

1. Get-DAClientExperienceConfiguration

Ensuring that the DirectAccess Client Settings group policy has been applied to the client is one of the first steps in troubleshooting failed DirectAccess connections. While it is possible to use gpresult to do this, using the Get-DAClientExperienceConfiguration PowerShell command is much simpler. If DirectAccess client settings have been applied, the output of the command will include information such as the IPsec tunnel endpoint IPv6 addresses and the Network Connectivity Assistant (NCA) corporate resource URL. If DirectAccess client settings have not been applied, this information will be missing.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 1. DirectAccess Client Settings group policy successfully applied.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 2. DirectAccess Client Settings group policy not applied.

2. Get-NetIPHttpsState

Performance improvements first introduced in Windows 8 have made IP-HTTPS the IPv6 transition technology of choice when it comes to supporting DirectAccess client connectivity. Also, if the DirectAccess server is located behind an edge device performing Network Address Translation (NAT), IP-HTTPS is the only supported transition technology. Using the Get-NetIPHttpsState PowerShell command, the DirectAccess administrator can quickly determine if the IP-HTTPS connection was successful. If it was not, the command will return an error code and interface status that will indicate why the IP-HTTPS connection was unsuccessful.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 3. Get-NetIPHttpsState

3. Get-NetIPHttpsConfiguration

When troubleshooting IP-HTTPS connection failures, it is necessary to obtain additional information to continue the troubleshooting process. Using the Get-NetIPHttpsConfiguration PowerShell command, the DirectAccess administrator can obtain the public hostname for the DirectAccess server and ensure that the name resolves to the correct IP address in DNS and that it is reachable on TCP port 443.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 4. Get-NetIPHttpsConfiguration

4. Resolve-DnsName

Using the Resolve-DnsName PowerShell command is crucial when performing any name resolution tasks on the DirectAccess client. This is because Resolve-DnsName is aware of the Name Resolution Policy Table (NRPT) and will direct name resolution requests accordingly. Tools like nslookup are DNS server testing tools and are unaware of the NRPT. Typically they do not yield expected results when testing name resolution on a DirectAccess client.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 5. Name resolution results from Resolve-DnsName and nslookup.

5. Get-DnsClientNrptPolicy

Often the cause of DirectAccess client connectivity issues is a misconfigured NRPT. Using the Get-DnsClientNrptPolicy PowerShell command the DirectAccess administrator can validate that name resolution requests for host names in any internal namespaces are being sent to the DirectAccess DNS64 IPv6 address.

Top 5 DirectAccess Troubleshooting PowerShell Commands

Figure 6. Get-DnsClientNrptPolicy

Additional Resources

Top 5 DirectAccess Troubleshooting Tips

Troubleshooting Name Resolution Issues on DirectAccess Clients

Learn PowerShell in a Month of Lunches Book by Don Jones and Jeff Hicks

Implementing DirectAccess with Windows Server 2016 Book

Planning and Implementing DirectAccess with Windows Server 2016 Video Training Course

Managing and Supporting DirectAccess with Windows Server 2016 Video Training Course

 

 

Uninstalling and Removing DirectAccess

Uninstalling and Removing DirectAccess This web site is primarily dedicated to installing, configuring, managing, and troubleshooting DirectAccess on Windows Server 2012 R2 and Windows Server 2016. However, there’s little documentation on how to properly uninstall and remove DirectAccess. This post provides guidance for gracefully uninstalling and removing DirectAccess after it has been deployed.

DirectAccess Clients

It is recommended that all clients be deprovisioned prior to decommissioning a DirectAccess deployment. This is especially true if the Network Location Server (NLS) is hosted on the DirectAccess server itself. Remove all client computers from the DirectAccess client security group or unlink DirectAccess client settings GPOs (but don’t delete them!) from any OUs where they are applied. Allow sufficient time for all clients to process security group membership changes and update group policy before uninstalling DirectAccess.

Network Location Server

If the NLS is installed separate from the DirectAccess server, it is recommended that it remain online for a period of time after DirectAccess has been decommissioned. Clients will be unable to access local resources if they still have DirectAccess client settings applied and the NLS is offline. Keeping the NLS online prevents this from happening. If this does happen, you’ll need to delete the Name Resolution Policy Table (NRPT) on the client to restore connectivity. To do this, run the following command in an elevated PowerShell command window and restart the computer.

Get-Item -Path “HKLM:\SOFTWARE\Policies\Microsoft\Windows NT\DNSClient\DnsPolicyConfig” | Remove-Item -Confirm:$false

Uninstall DirectAccess

It is not recommended to decommission DirectAccess by simply turning off all DirectAccess servers and manually deleting all of the associated group policy objects (GPOs) in Active Directory. A better way is to gracefully remove DirectAccess using the GUI or PowerShell.

To uninstall DirectAccess using the GUI, open the Remote Access Management console, highlight DirectAccess and VPN, and then click Remove Configuration Settings in the Tasks pane.

Uninstalling and Removing DirectAccess

Alternatively, DirectAccess can be removed by running the following command in an elevated PowerShell command window.

Uninstall-RemoteAccess -Force

Additional Resources

DirectAccess Network Location Server (NLS) Guidance

DirectAccess Network Location Server (NLS) Deployment Considerations for Large Enterprises

Implementing DirectAccess with Windows Server 2016

DirectAccess DNS Not Working Properly

Name resolution and proper DNS server configuration is vital to the functionality of DirectAccess. When performing initial configuration of DirectAccess, or making changes to the DNS server configuration after initial configuration, you may notice the operations status for DNS indicates Critical, and that the operations state shows Server responsiveness.

DirectAccess DNS Not Working Correctly

Highlighting the DNS server on the Operations Status page and viewing the details shows that DNS is not working properly with the following error message:

None of the enterprise DNS servers <IPv6_address> used by DirectAccess
clients for name resolution are responding. This might affect DirectAccess
client connectivity to corporate resources.

DirectAccess DNS Not Working Correctly

There are a number of things that can contribute to this problem, but a common cause is an error made when assigning a DNS server to a specific DNS suffix. An inexperienced DirectAccess administrator might specify the IPv4 address of an internal corporate DNS server, which is incorrect. The DNS server IPv4 address should be the address assigned to the DirectAccess server’s internal network interface.

The best way to ensure that the DNS server is configured correctly for DirectAccess is to delete the existing entry and then click Detect.

DirectAccess DNS Not Working Correctly

An IPv6 address will be added automatically. This is the IPv6 address of the DNS64 service running on the DirectAccess server, which is how the DNS server should be configured for proper DirectAccess operation.

DirectAccess DNS Not Working Correctly

Once the changes have been saved and applied, the DNS server should once again respond and the status should return to Working.

DirectAccess DNS Not Working Correctly

Unable to Install DirectAccess Hotfix KB2953212 to Disable NRPT

Last year I wrote about Microsoft hotfix KB2953212 that that allowed users to disable the Name Resolution Policy Table (NRPT) on a DirectAccess client. This hotfix addressed a specific scenario where a DirectAccess client on the internal corporate network could not connect to local resources due to Network Location Server (NLS) unreachability.

When installing this update, you many encounter the following error message:

Windows Update Standalone Installer
The update is not applicable to your computer

Unable to Install DirectAccess Hotfix KB2953212 to Disable NRPT

This occurs because the KB2953212 hotfix was included in KB3000850, the November 2014 update rollup for Windows 8.1 and Windows Server 2012 R2. You can verify this by opening the Control Panel and selecting Programs and then clicking View installed updates under Programs and Features.

Unable to Install DirectAccess Hotfix KB2953212 to Disable NRPT

If you have the November 2014 update rollup installed there is no need to install KB2953212, as that hotfix is already included in the rollup.

Hotfix Available to Disable NRPT on Windows 8.x DirectAccess Clients

Updated April 9, 2015: The hotfix referred to in this article is now included in the November 2014 update rollup for Windows 8.1 and Windows Server 2012 R2. You will receive an error message when installing this update on Windows 8.x clients with the update rollup installed. More details here.

The Network Location Server (NLS) is a critical infrastructure component for DirectAccess deployments. The NLS is used by DirectAccess clients to determine if the client is located inside or outside of the corporate network. If the NLS becomes unavailable, DirectAccess clients that are already outside the corporate network are unaffected. However, DirectAccess clients that are inside the corporate network will mistakenly believe that they are outside and the Name Resolution Policy Table (NRPT) will be enabled, forcing name resolution requests for hosts in the internal namespace to be sent to the DNS64 service running on the DirectAccess server. If the DirectAccess server is unreachable from the internal network (a common scenario for a variety of reasons), DirectAccess clients inside the corporate network will be unable to connect to any local network resources by name until the NLS is once again reachable.

Configuring the Network Connectivity Assistant to Allow DirectAccess clients to use local name resolution does not resolve this issue. Although it sounds intuitive, it doesn’t resolve this specific issue where the NLS is unreachable.

Hotfix Available to Disable NRPT on Windows 8.x DirectAccess Clients

When the option to Allow DirectAccess clients to use local name resolution is enabled, the client can only choose to disconnect (use local name resolution) after it has successfully established a connection to the DirectAccess server. If the DirectAccess connection shows that it is still connecting, the option to disconnect is not available.

Hotfix Available to Disable NRPT on Windows 8.x DirectAccess Clients

To address this issue, Microsoft has released update KB2953212 for Windows 8.x clients that allows the disabling of the NRPT regardless if the client has successfully established a DirectAccess connection. With this update, if a DirectAccess client is located on the corporate network and is unable to reach the NLS, the user will be able to disable the NRPT (effectively disconnect DirectAccess) and once again connect to resources on the corporate network.
Hotfix Available to Disable NRPT on Windows 8.x DirectAccess Clients

This update is certainly no excuse not to deploy your NLS in a highly-available configuration using Windows Network Load Balancing (NLB) or a third-party external load balancer (hardware or software), but it can be a life-saver if your NLS becomes unavailable for any reason. I’d recommend deploying this update to all of your Windows 8.x DirectAccess clients soon.

For more information and to download the hotfix, click here.

Troubleshooting Name Resolution Issues on DirectAccess Clients

When troubleshooting name resolution issues on a Windows client, NSlookup is an essential tool. However, it is important to understand that using NSlookup on a DirectAccess client might not always work as you expect. Although using NSlookup on a DirectAccess client will work normally when the client is on the corporate network, it will not provide the correct results to queries for internal hostnames when the DirectAccess client is outside of the corporate network without taking additional steps. This is because when a DirectAccess client is outside the corporate network, the Name Resolution Policy Table (NRPT) is enabled. The NRPT provides policy-based name resolution routing for DirectAccess clients, sending name resolution requests for certain namespaces to specific DNS servers. You can view the NRPT on a Windows 8.x DirectAccess client by issuing the following PowerShell command:

Get-DnsClientNrptPolicy

Troubleshooting Name Resolution Issues on DirectAccess Clients

You can view the NRPT on a Windows 7 DirectAccess client by issuing the following netsh command:

netsh namespace show policy

Troubleshooting Name Resolution Issues on DirectAccess Clients

Here you’ll notice that the namespace .lab.richardhicks.net is configured to use the DNS64 service running on the DirectAccess server at 2002:62bd:d898:3333::1. Notice also that the host nls.lab.richardhicks.net is not configured to use a DNS server. This effectively exempts this host from the NRPT, forcing name resolution requests for this Fully-Qualified Domain Name (FQDN) to be delivered to the DNS servers configured on the network adapter.

A Working Example

With the NRPT enabled, which occurs whenever the DirectAccess client is outside of the corporate network, a name resolution request for app1.lab.richardhicks.net would be sent to the DNS64 service on the DirectAccess server. A name resolution request for technet.microsoft.com would be sent to the DNS servers assigned to the network adapter because the NRPT contains no entry for this namespace. And even though the host nls.lab.richardhicks.net is a part of the internal namespace, a name resolution request for this host would also be sent to the DNS servers assigned to the network adapter because it has been specifically exempted from the NRPT.

NSlookup

The NSlookup utility is unaware of the NRPT. Whenever you use NSlookup it will, by default, automatically send queries directly to the DNS servers configured on the network adapter, regardless of the NRPT. If you wish to use NSlookup to test name resolution for external hostnames, use it as you normally would. However, if you wish to use NSlookup to resolve internal hostnames over the DirectAccess connection, you will need to tell NSlookup to use the DNS64 service running on the DirectAccess server. You can do this by running NSlookup interactively and using the server command to point it to the IPv6 address of the DNS64 service, which you can find in the NRPT.

Troubleshooting Name Resolution Issues on DirectAccess Clients

This also applies to the PowerShell cmdlet Resolve-DNSname. Here you’ll use the -Server switch to specify the DNS64 server’s IPv6 address.

Resolve-DNSName –Server <DNS64_IPv6_Address> app1.lab.richardhicks.net

Troubleshooting Name Resolution Issues on DirectAccess Clients

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