Sometimes you need to update older server says Server 2003 or older and you cannot use Powershell as its not installed, but you can use WMI. here is now....
$servers = get-content ./servers.txt
foreach($server in $servers)
{
Write-Output "Connect to $server..."
$nics = Get-WMIObject Win32_NetworkAdapterConfiguration -computername $servers | where { $_.IPEnabled -eq "TRUE"}
$newDNS = "8.8.8.8","8.8.4.4"
foreach($nic in $nics)
{
Write-output "`tExisting DNS Servers " $nic.DNSServerSearchOrder
$x = $nic.SetDNSServerSearchOrder($newDNS)
if($x.ReturnValue -eq 0)
{
Write-Output "`tSuccessfully Changed DNS Servers on " $server
}
else
{
Write-Output "`tFailed to Change DNS Servers on " $server
}
}
}