Ping then DNS lookup before I purge an asset - powershell

Question

So I am trying to Purge IPs from tool that we use. Before I can purge the assets we need to make sure the host is not pingable and not in DNS. I am new to PS and cant seem to wrap my head around on doing this. Any help is greatly appreciated. I have been doing this as a manual process by pinging the list of IPs and hostnames and doing a nslookup in cmd prompt before selecting the IPs that are needing to be removed. I have about 13k IPs left to do.
Update:
I want to implement this portion into it. Where In cell A it will have the IP
cell B will let me know if it is up or down. And Cell D will let me know if it is DNS aswell. Below is the script I got for pinging and checking if up or down and checking AD to see if the hostname is still in AD. I want it similar to this.. Please excuse my english
$path = ".\results.xls"
$objExcel = new-object -comobject excel.application
if (Test-Path $path)
{
$objWorkbook = $objExcel.WorkBooks.Open($path)
$objWorksheet = $objWorkbook.Worksheets.Item(1)
}
else {
$objWorkbook = $objExcel.Workbooks.Add()
$objWorksheet = $objWorkbook.Worksheets.Item(1)
}
$objExcel.Visible = $True
#########Add Header####
$objWorksheet.Cells.Item(1, 1) = "HostName"
$objWorksheet.Cells.Item(1, 2) = "Result"
$objWorksheet.Cells.Item(1, 3) = "MachineIP"
$objWorksheet.Cells.Item(1, 4) = "Active Directory"
$machines = Get-Content .\machinelist.txt
$row=2
$machines | foreach-object{
$ping = $null
$iname = $null
$machine = $_
$ping = Test-Connection $machine -Count 1 -ea silentlycontinue
$checkAD = try {$comp = Get-ADComputer -Identity $machine -ErrorAction
Stop
if ($comp){"Yes"}else{throw}
}
catch {"No"}
$objWorksheet.Cells.Item($row,4) = $checkAD
if($ping){
$objWorksheet.Cells.Item($row,1) = $machine
$objWorksheet.Cells.Item($row,2) = "UP"
$iname = $ping.IPV4Address.IPAddressToString
$objWorksheet.Cells.Item($row,3) = $iname
$row++}
else {
$objWorksheet.Cells.Item($row,1) = $machine
$objWorksheet.Cells.Item($row,2) = "DOWN"
$row++}
}

Answer 1

Here's a start, using Test-Connection and Resolve-DnsName, assuming you have a list of hosts' IP and name separated by a space, with a carriage return between each host:
$Assets = #"
127.0.0.1 localhost
255.255.255.255 fakehost
"#
$FailedPing = #()
$NoDNS = #()
$Assets -split "`r" | %{
$ipaddress = ($_.split(' ')[0]).trim()
$hostName = ($_.split(' ')[1]).trim()
Write-Host "IP: $ipaddress HOST: $hostName "
Try {
Test-Connection -ComputerName $ipaddress -Count 2 -ErrorAction Stop | Out-Null
}Catch {
$FailedPing += [pscustomobject]#{IP=$ipaddress; HostName = $hostName}
}
Try {
Resolve-DnsName -Name $hostName -ErrorAction Stop | Out-Null
}Catch {
$NoDNS += [pscustomobject]#{HostName = $hostName;Problem = $Error[0].Exception}
}
}
$FailedPing | ft
$NoDNS | ft