WMI/netsh to add DNS servers on network adapters

How to add DNS servers – or resolvers – to a Windows Server network adapter, or interface using WMI and the netsh command. This one is quite old but may come in handy sometimes. In this example we use Google’s Public DNS server addresses and localhost to add as DNS Servers on our server.

WMI and netsh to add DNS servers on network adapters for IPv4 and IPv6 addresses

Image of a phone book. Domain Name Servers (DNS) are the Internet's equivalent of a phone book
Domain Name Servers (DNS) are the Internet’s equivalent of a phone book. They maintain a directory of domain names and translate them to Internet Protocol (IP) addresses.

The WMI class only adds IPv4 addresses on interfaces. Therefor we use netsh for IPv6. The class Win32_NetworkAdapter is used to lookup the interface name and that interface is configured with the Win32_NetworkAdapterConfiguration WMI class.

AddDnsServers.ps1:

[array]$nics = Get-WmiObject -Class Win32_NetworkAdapterConfiguration -Filter "IPEnabled=true"
$dnsservers = "127.0.0.1", "8.8.8.8", "8.8.4.4"
$nics[0].SetDNSServerSearchOrder($dnsservers)
$index = $nics[0].index
$adapter = (Get-WmiObject -Class Win32_NetworkAdapter -Filter "DeviceID=$index").NetConnectionID

netsh interface ipv6 set dns "$adapter" static "2001:4860:4860::8888" primary
netsh interface ipv6 add dns "$adapter" "2001:4860:4860::8844" index=2

If you want to add more than two DNS name servers, increase the index number:

netsh interface ipv6 set dns "$adapter" static "::1" primary
netsh interface ipv6 add dns "$adapter" "2001:4860:4860::8888" index=2
netsh interface ipv6 add dns "$adapter" "2001:4860:4860::8844" index=3

Note: The Win32_NetworkAdapter class is deprecated. Use the MSFT_NetAdapter class instead.

In a multi NIC environment, set DNS servers for one active network card only

If your server has more than one network cards – or adapters – and suppose you want to change DNS servers only on active connected interfaces, then you can use something like:

$adapter = ( Get-NetAdapter | where { $_.Status -like "Up" } ).Name
netsh interface ipv4 set dns "$adapter" static "8.8.8.8" primary
netsh interface ipv4 add dns "$adapter" "8.8.4.4" index=2
netsh interface ipv4 add dns "$adapter" "208.67.222.222" index=3
netsh interface ipv6 set dns "$adapter" static "2001:4860:4860::8888" primary
netsh interface ipv6 add dns "$adapter" "2001:4860:4860::8844" index=2
netsh interface ipv6 add dns "$adapter" "2620:0:ccc::2" index=3

if ( $env:computername.tolower() -like "ad*" ) {
	write-host "[*] this is a Domain Controller! Add localhost as well, as last"
	netsh interface ipv4 add dns "$adapter" "127.0.0.1" index=4
	netsh interface ipv6 add dns "$adapter" "::1" index=4
}

Write-Host "DNS resolvers changed"

Substitute ad* for your domain controllers host names.

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