Why aren't my DNS queries forwarded to the DNS servers set on my Client VPN endpoint?

Short description

When you connect a client to a Client VPN endpoint with a target DNS server, Client VPN forwards queries to the target DNS server. If Client VPN forwards DNS queries to the client machine's local server instead of your Client VPN endpoint's server, then your binding order is faulty.

On machines that run Windows with faulty binding order, OpenVPN clients use the default network adapter's DNS settings instead of your VPN adapter's settings.

Resolution

Modify your interface’s interface metric value to change Windows Registry’s binding order to prefer the TAP-Windows Adapter V9 terminal access point adapter.

Note: Your interface’s interface metric property value determines Windows Registry's binding order. Lower interface metric values receive higher priority when your network selects an interface to route through.

To modify the interface metric property value, use Microsoft Command Prompt or PowerShell, or you can use the Control Panel in Windows.

Use Microsoft Command Prompt or PowerShell to modify the interface metric value

Complete the following steps:

1. Use the Client VPN service to connect to the Client VPN endpoint.

2. Open Command Prompt or PowerShell in Administrator mode.

3. Run ipconfig /all to get a list of adapters on your machine.
   -or-
   Run the following Get-NetIPInterface command:

   Get-NetIPInterface -AddressFamily IPv4 |  
   Sort-Object -Property InterfaceMetric |  
   Format-Table -Property InterfaceIndex, InterfaceAlias, @{Label="InterfaceDescription"; Expression={(Get-NetAdapter -InterfaceIndex $_.InterfaceIndex).InterfaceDescription}}, InterfaceMetric, ConnectionState

4. Note the interface number that corresponds with the TAP-Windows Adapter V9 adapter.

5. Run the command that corresponds with your operating system (OS).
   Windows 11:

   netsh interface ipv4 set interface example-interface-number metric=1

   Windows 10 and 11:

   Set-NetIPInterface --InterfaceIndex example-interface-number --InterfaceMetric 1

   Note: Replace example-interface-number with the interface number that you noted in step 3.

6. Run the following command to check the preferred DNS servers:

   netsh interface ip show config

Use Control Panel in Windows to modify the interface metric value

Complete the following steps:

1. Open Control Panel.
2. Choose Network and Internet, and then choose Network Connections.
3. Right-click the TAP-Windows Adapter V9 tap adapter.
4. Choose Properties, and then choose Internet Protocol Version 4.
5. Choose Properties, and then choose Advanced.
6. Clear the Automatic Metric box.
7. Enter 1 for Interface Metric.
8. Choose OK.