Mapping Networks with PowerShell

Mapping Networks with PowerShell

Part of maintaining clients is keeping track of the various networks involved in managing that client. It's important to know where computers are on the network to be able to support them. So here's a quick script, using PSAtera and PSWriteHTML to create a diagram mapping out what the public address is for agents.

In the diagram output the red nodes are public addresses, green nodes are network IDs and the blue nodes are the agents. Since Atera doesn't make the subnet mask available, I can't determine the true network ID, so the logic is just based off of the reserved IPv4 private networks for class A, B, and C networks.

The Script

Import-Module PSAtera
Import-Module PSWriteHTML

function Map-Agents($CustomerID) {
  # Get all Atera Agents for the customer
  $Agents = Get-AteraAgents -CustomerID $CustomerID
  New-Html -TitleText "Atera Agent Map" -Online -FilePath $PSScriptRoot\Atera-Agents.html {
    New-HTMLTabStyle -SlimTabs
    New-HTMLTab -Name "Atera Agents" {
      New-HTMLSection -HeaderText "Atera Networks" {
        New-HTMLPanel {
          New-HTMLDiagram -Height 'calc(85vh)' {
            New-DiagramOptionsPhysics -RepulsionNodeDistance 150 -Solver repulsion
            # Generate Level 1: Public network
            $Agents | Select-Object ReportedFromIP -Unique | ForEach-Object {
              New-DiagramNode -Label $_.ReportedFromIP -Level 1 -ColorBackground Red

            $PrivateNetworks = @()
            foreach($Agent in $Agents) {
              # Ignore any self-assigned IP addresses
              $Agent.IPAddresses | Where-Object { !($_.StartsWith("169.254.")) } | ForEach-Object {
                $Address = [IPAddress]$_
                $AddressBytes = $Address.GetAddressBytes()
                $Network = ""
                # Stupidly get the Network ID based on the Class of IP address
                if ($AddressBytes[0] -eq 10) { # Class A
                  $Network = ""
                } elseif ($AddressBytes[0] -eq 172 -and $AddressBytes[1] -ge 16 -and $AddressBytes[1] -le 31) { # Class B
                  $Network = "172.16.$($AddressBytes[2]).0/16"
                } elseif ($AddressBytes[0] -eq 192 -and $AddressBytes[1] -eq 168) {
                  $Network = "192.168.$($AddressBytes[2]).0/24"                
                # Create the Diagram node for the network ID under the public IP address
                if ($PrivateNetworks -notcontains "$Network,$($Agent.ReportedFromIP)") { 
                  $PrivateNetworks += "$Network,$($Agent.ReportedFromIP)"
                  New-DiagramNode -Label $Network -Id "$Network,$($Agent.ReportedFromIP)" -To $Agent.ReportedFromIP -Level 2 -ArrowsToEnabled -ColorBackground Green
                # Create the Diagram node for the agent under it's corrent network ID
                New-DiagramNode -Label "$($Agent.MachineName)`t$($Address.IPAddressToString)" -Level 3 -To "$Network,$($Agent.ReportedFromIP)" -ArrowsToEnabled
  } -ShowHTML
Full code for the Map-Agents command

Save the code above to "Map-Agents.ps1" and then execute the following changing the Customer ID to whichever you'd like to use:

> . .\Map-Agents.ps1
> Map-Agents -CustomerID 17

The diagram will generate and open in your default browser.