I’ve noticed that occasionally my OpenVPN connection fails to resolve host names for systems at the other end of the tunnel. If I check the DHCP settings I can see I am being pushed the DNS servers for the remote end, but nslookup fails to use them. This is to do with the binding order. In previous version of Windows you could adjust the binding order, but on Windows 10 this option has been removed. To ensure your OpenVPN Interface appears before your other adapters you need to use some PowerShell to change the InterfaceMetric. The lower the number the higher the priority. View the current interface metrics:
PS C:> Get-NetIPInterface
ifIndex InterfaceAlias AddressFamily NlMtu(Bytes) InterfaceMetric Dhcp ConnectionState PolicyStore
------- -------------- ------------- ------------ --------------- ---- --------------- -----------
10 isatap.{38D4AE9A-7FAC-4EA3-9... IPv6 1280 75 Disabled Disconnected ActiveStore
17 isatap.domain.local IPv6 1280 75 Enabled Disconnected ActiveStore
7 Teredo Tunneling Pseudo-Inte... IPv6 1280 75 Enabled Disconnected ActiveStore
6 VirtualBox Host-Only Network IPv6 1500 25 Enabled Connected ActiveStore
21 isatap.whalesanctuary.co.uk IPv6 1280 75 Disabled Disconnected ActiveStore
20 Ethernet 2 IPv6 1500 75 Enabled Connected ActiveStore
1 Loopback Pseudo-Interface 1 IPv6 4294967295 75 Disabled Connected ActiveStore
14 Local Area Connection* 2 IPv6 1500 25 Disabled Disconnected ActiveStore
5 Ethernet IPv6 1500 5 Disabled Disconnected ActiveStore
19 Wi-Fi IPv6 1500 30 Enabled Connected ActiveStore
6 VirtualBox Host-Only Network IPv4 1500 25 Disabled Connected ActiveStore
20 Ethernet 2 IPv4 1500 75 Enabled Connected ActiveStore
1 Loopback Pseudo-Interface 1 IPv4 4294967295 75 Disabled Connected ActiveStore
14 Local Area Connection* 2 IPv4 1500 25 Enabled Disconnected ActiveStore
5 Ethernet IPv4 1500 5 Enabled Disconnected ActiveStore
19 Wi-Fi IPv4 1500 30 Enabled Connected ActiveStoreUse the ifindex listed against your OpenVPN adapter. In my case it was 20 for “Ethernet 2” I then just raised this from 75 to 10:
PS C:\> Set-NetIPInterface -InterfaceIndex 20 -InterfaceMetric 10References: https://technet.microsoft.com/en-us/library/hh826125(v=wps.630).aspx For Windows 7 You’ll need to raise the “[Remote Access Connections]” above the “Local Area Connection” using the following reference. References: https://support.microsoft.com/en-gb/help/2526067