Update-StaticDNSServers.ps1

<#
        .SYNOPSIS
            Updates static DNS servers on Windows devices

        .DESCRIPTION
            Input file should have list of devices by hostname separated by lines.
            This script will attempt to update the static DNS servers on each device listed.

        .NOTES 
            Author: Dan Zabinski, https://github.com/DanZab
            Date: 5/3/2019

#>


# Configuration Variables

# Input files containing target devices
$inputFile = "C:\Temp\ServerList.txt"
# The Static DNS servers you would like devices to be set to
$DnsServers =@("10.0.0.1","10.0.0.1") 


$ComputerList = Get-Content $inputFile
 
ForEach ($ComputerName in $ComputerList) { 

	#Ping to test for connectivity to the computer object
    $Result =  Get-WmiObject win32_pingstatus -Filter "address='$ComputerName'" 
	
    if ($Result.StatusCode -eq 0) {
	
		#This searches for each network adapter where the type is Ethernet, can be modified to isolate other adapters
        $RemoteNics = Get-WmiObject -class win32_networkadapter -Computer $ComputerName | Where-Object {$_.AdapterType -like "ethernet*"}
		
		
		#This loop is here in case there are multiple network adapters
		ForEach ($RemoteNic in $RemoteNics) { 
		
			$NicIndex = $RemoteNic.index
			$NicName = $RemoteNic.name
			$DnsServerList = $(Get-WmiObject win32_networkadapterconfiguration -Computer $ComputerName -Filter 'IPEnabled=true' | Where-Object {$_.index -eq $NicIndex}).dnsserversearchorder 
			
			
			#This variable is available if you need to reference the current primary DNS server
			#$PrimaryDnsServer = $DnsServerList | Select-Object -First 1 
			
			if ($DnsServerList -ne $null) {
			
				Write-Host "Changing DNS server IPs on $ComputerName" -b "Yellow" -ForegroundColor "black"
				Write-Host "Interface Name $NicName" -b "Yellow" -ForegroundColor "black"
				Write-Host "Old servers - $DnsServerList" -b "Yellow" -ForegroundColor "black"
				
				$Change = Get-WmiObject win32_networkadapterconfiguration -Computer $ComputerName | Where-Object {$_.index -eq $NicIndex} 
				$Change.SetDnsServerSearchOrder($DnsServers) | Out-Null
				
				$Changes = $(Get-WmiObject win32_networkadapterconfiguration -Computer $ComputerName -Filter 'IPEnabled=true' | Where-Object {$_.index -eq $NicIndex}).dnsserversearchorder 
				Write-Host "$ComputerName's servers have been updated to $Changes" -ForegroundColor "Green"
				
			}
			Else {
				Write-Host "No DNS Servers on Nic Interface $NicName" -ForegroundColor "Yellow"
			}
		}
    } 
    Else {
        Write-Host "$ComputerName is down, cannot change IP address" -b "Red" -ForegroundColor "white" 
    } 
}