Get-PingSweep - super fast (~500ms) subnet ping sweep with option to resolve IP address

Get-PingSweep.ps1

# Inspiration from https://twitter.com/mrhvid/status/929717169130176512 @mrhvid @Lee_Holmes

function ResolveIp($IpAddress) {
    try {
        (Resolve-DnsName $IpAddress -QuickTimeout -ErrorAction SilentlyContinue).NameHost
    } catch {
        $null
    }
}

function Get-PingSweep {
    [CmdletBinding()]
    Param(
        [Parameter(Mandatory=$true)]
        [string]$SubNet,
        [switch]$ResolveName
    )
    $ips = 1..254 | ForEach-Object {"$($SubNet).$_"}
    $ps = foreach ($ip in $ips) {
        (New-Object Net.NetworkInformation.Ping).SendPingAsync($ip, 250)
        #[Net.NetworkInformation.Ping]::New().SendPingAsync($ip, 250) # or if on PowerShell v5
    }
    [Threading.Tasks.Task]::WaitAll($ps)
    $ps.Result | Where-Object -FilterScript {$_.Status -eq 'Success' -and $_.Address -like "$subnet*"} |
    Select-Object Address,Status,RoundtripTime -Unique |
    ForEach-Object {
        if ($_.Status -eq 'Success') {
            if (!$ResolveName) {
                $_
            } else {
                $_ | Select-Object Address, @{Expression={ResolveIp($_.Address)};Label='Name'}, Status, RoundtripTime
            }
        }
    }
}

<#
Get-PingSweep -SubNet '10.56.161'
Address        Status RoundtripTime
-------        ------ -------------
10.56.161.1   Success             2
10.56.161.48  Success             0
10.56.161.49  Success             0
10.56.161.51  Success             0
10.56.161.52  Success             0
10.56.161.53  Success             0
10.56.161.54  Success             1

Get-PingSweep -SubNet '10.56.161' -ResolveName
Address       Name                          Status RoundtripTime
-------       ----                          ------ -------------
10.56.161.1   b86-bop12-sw18.contoso.com   Success             3
10.56.161.48  it-box1-dhwin7.contoso.com   Success             1
10.56.161.49  it-box2-dhwin10.contoso.com  Success             0
10.56.161.51  it-dept1-uh7yg2.contoso.com  Success             0
10.56.161.52  ds101sync.contoso.com        Success             0
10.56.161.53                               Success             1
10.56.161.54  it-ithd-12tr889.contoso.com  Success             1

(Measure-Command -Expression {Get-PingSweep -SubNet '10.56.161' -ResolveName}).Milliseconds
441
#>

@aussiejack586 the code will just scan a /24 (255.255.255.0) subnet - you just enter the first 3 octets of the subnet as in the 2 examples.
So Get-PingSweep -SubNet '10.56.161' will scan IP addresses from 10.56.161.1 to 10.56.161.254.

@joegasper Thanks for the speedy response! I may be doing it wrong however I am getting this message.
Exception calling "WaitAll" with "1" argument(s): "One or more errors occurred."
At line:21 char:5

• [Threading.Tasks.Task]::WaitAll($ps)
  

• ~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~~
  

  • CategoryInfo : NotSpecified: (:) [], MethodInvocationException
  • FullyQualifiedErrorId : AggregateException

I get that error if I try something like:
Get-PingSweep -SubNet 192.168.1.56

The correct command would be:
Get-PingSweep -SubNet 192.168.1

Just give the command the first 3 numbers (octets).
That example will ping from 192.168.1.1 to 192.169.1.254 and list any responding IP addresses in that range.

Hi, the script is owesome thanks, but i have some problems.
Every time when i make a scan, different IP addresses are shown, for example:
Each time I am getting different result (list of active devices) somethink like:
Scan 1:
192.168.20.1
192.168.20.6
192.168.20.164

Scan 2:
192.168.20.1
192.168.20.6
192.168.20.31
192.168.20.164
Scan 3:

192.168.20.1
192.168.20.6
192.168.20.107
192.168.20.99

but i know that one device has 192.168.20.100 Address, and then when i manually make a ping 192.168.20.100
and make pingsweep again, then is Address in the list.

Scan 4:
192.168.20.1
192.168.20.6
192.168.20.107
192.168.20.100

My problem is actually, I need to know which devices are online, it seems that pingsweep is super fast but therfore unreliable.
Do you have any advice?
Thanks in advance!