Script to collect LLDP Information of all the hosts connected to vCenter

 

Challenge: To have a clean inventory of host to switch mapping, we had to gather the lldp information of all the ESXi hosts. It would be easier if the hosts are a few/ in a single digit. 

We had to find an easy and automated script which can generate the output.

 Pre-requisites:

1) Requires power-cli to be installed.

2) Install-Module -Name VMware.PowerCLI -Scope CurrentUser 

Powershell script:

 1) To ignore ssl certificate error

Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -Confirm:$true

 2) Script to connect to vCenter and provide valid credentials, and the script will provide the output in a csv format to the provided location, which can be customized.

 # Array of vCenter Server names or IP addresses
$vCenterServers = @("192.168.1.62") # Add all your vCenter Servers here

# Output file path
$OutputPath = "C:\Users\asyed\Documents\ESXi_LLDP_Report1.csv" # Change this to your desired output path

# --- Script Start ---

Write-Host "Connecting to vCenter Server(s)..." -ForegroundColor Green

# Connect to all specified vCenter Servers
# Using -Force to bypass certificate warnings for lab/test environments.
# In production, ensure proper certificate handling.
try {
    Connect-VIServer -Server $vCenterServers -WarningAction SilentlyContinue -ErrorAction Stop
    Write-Host "Successfully connected to vCenter Server(s)." -ForegroundColor Green
}
catch {
    Write-Error "Failed to connect to vCenter Server(s). Error: $($_.Exception.Message)"
    exit
}

$lldpReport = @()

Write-Host "Gathering LLDP information from ESXi hosts..." -ForegroundColor Green

# Get all ESXi hosts
$allEsxiHosts = Get-VMHost # Renamed the collection variable for clarity

if ($allEsxiHosts.Count -eq 0) {
    Write-Warning "No ESXi hosts found in the connected vCenter Server(s)."
}
else {
    # CHANGE THIS LINE: Use a different variable name for the loop, e.g., $esxiHost
    foreach ($esxiHost in $allEsxiHosts) {
        Write-Host "Processing host: $($esxiHost.Name)..." -ForegroundColor Cyan

        try {
            # Get the NetworkSystem view for the host
            $networkSystem = Get-View $esxiHost.ExtensionData.ConfigManager.NetworkSystem

            # Get physical NICs
            $physicalNics = $esxiHost.ExtensionData.Config.Network.Pnic

            if ($physicalNics.Count -eq 0) {
                Write-Warning "No physical NICs found for host $($esxiHost.Name)."
                continue
            }

            foreach ($pnic in $physicalNics) {
                $pnicDevice = $pnic.Device
                $networkHint = $null

                try {
                    $networkHint = $networkSystem.QueryNetworkHint($pnicDevice)
                }
                catch {
                    Write-Warning "Could not retrieve network hint for $($esxiHost.Name) - $($pnicDevice). Error: $($_.Exception.Message)"
                    continue
                }

                if ($networkHint) {
                    foreach ($hint in $networkHint) {
                        if ($hint.LldpInfo) {
                            $lldpInfo = $hint.LldpInfo
                            $managementAddress = ($lldpInfo.Parameter | Where-Object {$_.Key -eq "Management Address"}).Value
                            $systemName = ($lldpInfo.Parameter | Where-Object {$_.Key -eq "System Name"}).Value
                            $systemDescription = ($lldpInfo.Parameter | Where-Object {$_.Key -eq "System Description"}).Value
                            $portDescription = ($lldpInfo.Parameter | Where-Object {$_.Key -eq "Port Description"}).Value
                            $chassisId = $lldpInfo.ChassisId
                            $portId = $lldpInfo.PortId

                            $lldpEntry = [PSCustomObject]@{
                                VMHostName          = $esxiHost.Name
                                VMHostIP            = (Get-VMHostNetworkAdapter -VMHost $esxiHost | Where-Object {$_.ManagementTrafficEnabled -eq $true}).IP # Get management IP
                                PhysicalNic         = $pnicDevice
                                LLDP_ChassisID      = $chassisId
                                LLDP_PortID         = $portId
                                LLDP_PortDescription= $portDescription
                                LLDP_SystemName     = $systemName
                                LLDP_SystemDescription = $systemDescription
                                LLDP_ManagementAddress = $managementAddress
                            }
                            $lldpReport += $lldpEntry
                        }
                        elseif ($hint.ConnectedSwitchPort) {
                            Write-Verbose "CDP information found for $($esxiHost.Name) - $($pnicDevice). LLDP not present."
                        }
                        else {
                            Write-Verbose "No LLDP or CDP information found for $($esxiHost.Name) - $($pnicDevice)."
                        }
                    }
                }
            }
        }
        catch {
            Write-Error "An error occurred while processing host $($esxiHost.Name). Error: $($_.Exception.Message)"
        }
    }
}

Write-Host "Exporting LLDP information to CSV: $($OutputPath)..." -ForegroundColor Green

if ($lldpReport.Count -gt 0) {
    $lldpReport | Export-Csv -Path $OutputPath -NoTypeInformation -UseCulture
    Write-Host "LLDP report generated successfully at: $($OutputPath)" -ForegroundColor Green
}
else {
    Write-Warning "No LLDP information was collected to export."
}

Write-Host "Disconnecting from vCenter Server(s)..." -ForegroundColor Green
Disconnect-VIServer -Confirm:$false

Write-Host "Script finished." -ForegroundColor Green 

# --- Script End --- 

 

3) Once you get the output, return the invalid certificate action to false by running below command. 

Set-PowerCLIConfiguration -InvalidCertificateAction Ignore -Confirm:$false