For some reason I wanted to write a trace route script in PowerShell, but decided to run it through Google first to see if it had been done. Surprisingly few results came up, and as far as I can tell, only one true PowerShell script doing Trace Route without just being a wrapper for tracert or something similar: https://snoj.us/75/traceroute-with-starting-ttls/
Naturally I wanted to tweak it and give it my personal touch, and here is my result:
| function Trace-Route { | |
| <# | |
| .SYNOPSIS | |
| Trace the route between source computer and a target machine. | |
| .DESCRIPTION | |
| Trace the route between source computer and a target machine. | |
| .EXAMPLE | |
| Trace-Route Computer01 | |
| Perform trace route to Computer01 | |
| .EXAMPLE | |
| Trace-Route -Target http://www.microsoft.com -ResolveHostname | |
| Perform trace route to http://www.microsoft.com and try to resolve hostname for each hop. | |
| Note! This will slow down the function somewhat. | |
| .NOTES | |
| Author: Øyvind Kallstad | |
| Date: 28.10.2014 | |
| Version: 1.1 | |
| #> | |
| [CmdletBinding()] | |
| param( | |
| # Hostname or IP to trace to. | |
| [Parameter(Position = 0, ValueFromPipeline = $true)] | |
| [string] $Target = $env:COMPUTERNAME, | |
| # Set starting hop. | |
| [Parameter()] | |
| [int] $BeginHop = 1, | |
| # Set maximum number of hops. | |
| [Parameter()] | |
| [int] $MaxHops = 30, | |
| # Define timeout in milliseconds. | |
| [Parameter()] | |
| [int] $Timeout = 1000, | |
| # Try to resolve hostname for IP in each hop. | |
| [Parameter()] | |
| [switch] $ResolveHostname = $false | |
| ) | |
| # verify that we can reach target system | |
| try{ | |
| $ping = New-Object System.Net.NetworkInformation.Ping | |
| $pingResult = $ping.Send($Target) | |
| if(-not($pingResult.Status -eq 'Success')){ | |
| Write-Warning "Unable to resolve target system $Target" | |
| exit | |
| } | |
| } | |
| catch{ | |
| Write-Warning "Unable to resolve target system $Target" | |
| exit | |
| } | |
| # define some data to send | |
| $sendBytes = @([byte][char]'a'..[byte][char]'z') | |
| for($i = $BeginHop; $i -lt $MaxHops; $i++) { | |
| # define ping options; set start hop and fragmentation to true | |
| $pingOptions = new-object System.Net.NetworkInformation.PingOptions $i, $true | |
| # perform ping | |
| $pingReply = $ping.Send($Target, $Timeout, $sendBytes, $pingOptions) | |
| # get ip for current hop if possible | |
| if($pingReply.Address -ne $null){ | |
| $ip = $pingReply.Address | |
| } | |
| else{ | |
| $ip = '*' | |
| } | |
| # get roundtrip time | |
| $roundtripTime = $pingReply.RoundtripTime | |
| # get status | |
| $hopStatus = $pingReply.Status | |
| # resolve hostname | |
| if ($ResolveHostname) { | |
| try{ | |
| $resolvedHostname = "[$(([System.Net.Dns]::GetHostEntry($ip)).HostName)]" | |
| } | |
| catch{ | |
| $resolvedHostname = '' | |
| } | |
| } | |
| # create custom object and send to pipeline | |
| Write-Output ([PSCustomObject] [Ordered] @{ | |
| Hop = $i.ToString() | |
| IP = "$($ip) $($resolvedHostname)" | |
| Status = $hopStatus | |
| RoundtripTime = $roundtripTime | |
| }) | |
| # clean up | |
| Remove-Variable ip, roundtripTime, hopStatus, resolvedHostname –ErrorAction 'SilentlyContinue' | |
| # stop loop if current ip matches the target ip | |
| if($pingReply.Address -eq $pingResult.Address){break} | |
| } | |
| } |
