Get CDP info of multiple Esxi Hosts

Get_CDPinfo_of_Esxi_Hosts_v1.1.ps1

## Get CDP info of single/multiple Esxi hosts ##
## It's based on the original work of Jonathan Medd's script (https://www.jonathanmedd.net/2013/07/obtaining-cdp-info-via-powercli.html), I just add the Get-VMhost and Export-Csv option to find all the CDP info of the connected esxi hosts ##
## Author : Phyoe Wai Paing
## Country: Myanmar(Burma)
## Changed History :
## Version : 22.May.2016 : 1.0 : Initial release
##	   : 12.Apr.2022 : 1.1 : Add the validation of hostlist.txt file and export to csv by default in addition to displaying the result in the console

function Get-VMHostNetworkAdapterCDP {
<#
**********************************************************************
***** The function will exist if there is 1 disconnected Host ********
**********************************************************************
 .SYNOPSIS
 Function to retrieve the Network Adapter CDP info of a vSphere host.

 .DESCRIPTION
 Function to retrieve the Network Adapter CDP info of a vSphere host.

 .PARAMETER VMHost
 A vSphere ESXi Host object

.INPUTS
 System.Management.Automation.PSObject.

.OUTPUTS
 System.Management.Automation.PSObject.

.EXAMPLE
 PS> Get-VMHostNetworkAdapterCDP -VMHost ESXi01,ESXi02

 .EXAMPLE
 PS> Get-VMHost ESXi01,ESXi02 | Get-VMHostNetworkAdapterCDP

#>
[CmdletBinding()][OutputType('System.Management.Automation.PSObject')]

Param
 (

[parameter(Mandatory=$true,ValueFromPipeline=$true)]
 [ValidateNotNullOrEmpty()]
 [PSObject[]]$VMHost
 )

begin {

 $ErrorActionPreference = 'Stop'
 Write-Debug $MyInvocation.MyCommand.Name
 $CDPObject = @()
 }

process{

try {
 foreach ($ESXiHost in $VMHost){

if ($ESXiHost.GetType().Name -eq "string"){

 try {
 $ESXiHost = Get-VMHost $ESXiHost -ErrorAction Stop
 }
 catch [Exception]{
 Write-Warning "VMHost $ESXiHost does not exist"
 }
 }

 elseif ($ESXiHost -isnot [VMware.VimAutomation.ViCore.Impl.V1.Inventory.VMHostImpl]){
 Write-Warning "You did not pass a string or a VMHost object"
 Return
 }

$ConfigManagerView = Get-View $ESXiHost.ExtensionData.ConfigManager.NetworkSystem
 $PNICs = $ConfigManagerView.NetworkInfo.Pnic

foreach ($PNIC in $PNICs){

$PhysicalNicHintInfo = $ConfigManagerView.QueryNetworkHint($PNIC.Device)

if ($PhysicalNicHintInfo.ConnectedSwitchPort){

$Connected = $true
 }
 else {
 $Connected = $false
 }

$hash = @{

 VMHost = $ESXiHost.Name
 NIC = $PNIC.Device
 Connected = $Connected
 Switch = $PhysicalNicHintInfo.ConnectedSwitchPort.DevId
 HardwarePlatform = $PhysicalNicHintInfo.ConnectedSwitchPort.HardwarePlatform
 SoftwareVersion = $PhysicalNicHintInfo.ConnectedSwitchPort.SoftwareVersion
 MangementAddress = $PhysicalNicHintInfo.ConnectedSwitchPort.MgmtAddr
 PortId = $PhysicalNicHintInfo.ConnectedSwitchPort.PortId
 VlanID=$PhysicalNicHintInfo.ConnectedSwitchPort.Vlan
}
 $Object = New-Object PSObject -Property $hash
 $CDPObject += $Object
 }
 }
 }
 catch [Exception] {

 throw "Unable to retrieve CDP info"
 }
 }
 end {

$CDPObject | where { $_.Connected -eq $True } | ft VMHost,NIC,VlanID,Switch,Connected,PortId,MangementAddress,HardwarePlatform,SoftwareVersion -auto

# Uncomment the following line if you want to export to CSV sheet
$CDPObject | where { $_.Connected -eq $True } | select VMHost,NIC,VlanID,Switch,Connected,PortId,MangementAddress,HardwarePlatform,SoftwareVersion | export-csv .\CDP_Networkinfo.csv -notypeinfo
Write-Host "CDP Info exported to CDP_Networkinfo.csv"
 }
}

If ((Test-Path -Path .\hostlist.txt) -AND !([string]::IsNullOrWhiteSpace((Get-Content -Path .\hostlist.txt))))
	{
		$hostlist= Get-Content hostlist.txt
		Write-Host "Getting the CDP Info for $($hostlist.Count) hosts. Please wait..."
		$hostlist | Get-VMHostNetworkAdapterCDP
	}
else
	{
		$hostlist = Get-VMHost | ? { $_.ConnectionState -eq "Connected" }
		Write-Host "Getting the CDP Info for $($hostlist.Count) hosts. Please wait..."
		$hostlist | Get-VMHostNetworkAdapterCDP
	}