DNS Change

 <#
   .Description
    This Script contains an function which switches your dns to google.
    if you already use google dns is switches to the DHCP distributed dns

   #>


 # Self-elevate the script if required
    if (-Not ([Security.Principal.WindowsPrincipal] [Security.Principal.WindowsIdentity]::GetCurrent()).IsInRole([Security.Principal.WindowsBuiltInRole] 'Administrator')) {
        if ([int](Get-CimInstance -Class Win32_OperatingSystem | Select-Object -ExpandProperty BuildNumber) -ge 6000) {
         $CommandLine = "-File `"" + $MyInvocation.MyCommand.Path + "`" " + $MyInvocation.UnboundArguments
         Start-Process -FilePath PowerShell.exe -Verb Runas -ArgumentList $CommandLine

        }
       }


function WriteOldDns {
 Write-Host "Your previous DNS was:"
Get-DnsClientServerAddress -InterfaceAlias "Ethernet"
}



function WriteNewDns {
Write-Host "Your current DNS was:"
Write-Host "
InterfaceAlias               Interface Address Server Addressess
                             Index     Family
--------------               --------- ------- -----------------"

Get-DnsClientServerAddress -InterfaceAlias "Ethernet"
}



function setDnsToGoogle
{
    param
    (
        $interfacealias = "Ethernet"
    )
    $googleIP = @("8.8.8.8","8.8.4.4","2001:4860:4860::8888","2001:4860:4860::8844")
    $currentdns = Get-DnsClientServerAddress -InterfaceAlias $interfacealias
    foreach ($gip in $googleIP)
    {
        if(($currentdns).ServerAddresses -like $gip)
        {
            Set-DnsClientServerAddress -InterfaceAlias $interfacealias -ResetServerAddresses
            Clear-DnsClientCache

        }else
        {
        Set-DnsClientServerAddress -InterfaceAlias $interfacealias -ServerAddresses ("8.8.8.8","8.8.4.4","2001:4860:4860::8888","2001:4860:4860::8844")

        }
    }


}




WriteOldDns

setDnsToGoogle

Write-Host "

"

WriteNewDns

Start-Sleep -Seconds 10
Pause