Get-ServerDNS

#THIS SCRIPT IS UNTESTED

$report = ""
$servers = get-content "c:\users\$env:username\Documents\servers.txt"

foreach ($server in $servers)

{
    $ServerIsUP = Test-Connection -ComputerName $server -Count 3 -Quiet

        If ($ServerIsUP -eq $False)
        {
            write-host "$server is not available"
        }
        else
        {
            $addresses = [System.Net.Dns]::GetHostAddresses($server)
                foreach($a in $addresses)
                    {
                        $report +="{0},{1}`r`n" -f $server,$a.IPAddressToString
                    }#End $Addresses Loop
        }

     $report | out-file c:\users\$env:username\Documents\lookup.txt
}