Configure DNS Suffix for Specific Adapter in Regedit

This guide explains how to manually configure a connection-specific DNS suffix for an individual network adapter using the Windows Registry Editor (Regedit). By locating the target adapter’s unique Globally Unique Identifier (GUID) and modifying its corresponding interface parameters under the TCP/IP service key, you can enforce custom domain resolution settings directly at the registry level.

Step 1: Identify the Network Adapter’s GUID

To apply settings to a specific adapter, you first need its unique GUID:

  1. Press Win + R, type cmd, and press Enter.

  2. Run the following command:

    getmac /v /fo list

  3. Locate your target network adapter and note the string inside the braces under the Transport Name (for example: {12345678-ABCD-1234-ABCD-1234567890AB}).

Step 2: Open Registry Editor and Navigate to the Interface

  1. Press Win + R, type regedit, and press Enter.

  2. Navigate to the following registry path:

    HKEY_LOCAL_MACHINE\SYSTEM\CurrentControlSet\Services\Tcpip\Parameters\Interfaces

  3. Expand the Interfaces key to see subkeys named after adapter GUIDs.

  4. Click the subkey that matches the GUID identified in Step 1.

Step 3: Configure the DNS Suffix

  1. In the right-hand pane of the target GUID subkey, look for a string value (REG_SZ) named Domain.
  2. If Domain does not exist:
    • Right-click an empty area in the right pane.
    • Select New > String Value.
    • Name the value Domain.
  3. Double-click the Domain string value.
  4. In the Value data field, enter your desired DNS suffix (e.g., corp.example.com).
  5. Click OK to save the value.

(Optional) If you want to ensure dynamic DHCP settings do not overwrite this value, check if a DhcpDomain string exists. The static Domain key will take precedence over DhcpDomain, but setting Domain directly ensures the manual override remains active.

Step 4: Apply and Verify Changes

To apply the registry configuration without rebooting the system:

  1. Open Command Prompt as Administrator.

  2. Restart the TCP/IP stack and refresh the DNS client cache:

    ipconfig /flushdns
ipconfig /registerdns

  3. Verify that the new suffix is assigned to the adapter:

    ipconfig /all

  4. Look under the specific adapter section for the Connection-specific DNS Suffix line to confirm it displays your newly configured domain.