Get Free IP Address

# Define the subnet prefix
$subnet = "10.60.1."

# Initialize an array to store IPs that have neither DNS records nor respond to ping
$noDnsNoPingHosts = @()

# Define the total number of IPs to check within the subnet range
$totalIPs = 245

# Loop through each IP in the range, starting from 11 up to the total IP count
for ($i = 11; $i -le $totalIPs; $i++) {
    # Construct the full IP address by appending the counter to the subnet prefix
    $ip = "$subnet$i"
    
    # Display a progress bar with the percentage of IPs processed
    Write-Progress -Activity "Pinging IPs" -Status "Processing $ip" -PercentComplete (($i / $totalIPs) * 100)
    
    # Test if the IP responds to a ping request
    if (!(Test-Connection -ComputerName $ip -Count 1 -Quiet)) {
        # If the ping fails, perform an additional check to retrieve hostname via ping -a
        $hostname = (Test-Connection -ComputerName $ip -Count 1 -AsJob | Receive-Job | Select-Object -ExpandProperty Address)
        
        # Perform a DNS lookup to verify if there's a DNS entry for the IP
        $dnsResult = nslookup $ip 2>&1
        if ($dnsResult -match "can't find") {
            # If both ping and DNS lookup fail, add the IP to the no DNS/no ping list
            $noDnsNoPingHosts += $ip
        }
    }
}

# Output the list of IPs that have no DNS record and failed the ping test
$noDnsNoPingHosts

# Retrieve the first IP from the list of IPs that have no DNS entry and no ping response
$firstNoDnsNoPingIP = $noDnsNoPingHosts | Select-Object -First 1

# Output the first IP from the list, or use it in another script as needed
$firstNoDnsNoPingIP

# Display the first IP from the list with a label for clarity
Write-Output "First No DNS/No Ping IP: $firstNoDnsNoPingIP"