Getting CDP (Cisco Discovery Protocol) information via PowerShell on specified list of ESXi hosts

get-cdp-short.ps1

<#param([string]$VMhost, [string]$Cluster, [string]$VCServer)

If ($VMhost) {$vmh = Get-VMHost -Name $VMhost} 
If ($Cluster) {$vmh = Get-Cluster $Cluster | Get-VMHost}
If ($VCServer) {$vmh = Get-VMhost -Server $VCServer}
#>
param(
  [Parameter(ValueFromPipeline)]
  [VMware.VimAutomation.ViCore.Impl.V1.Inventory.VMHostImpl[]]$VMHost = $(Get-VMHost)
)

function collectProperties {
  param (
    [VMware.Vim.ServiceInstance]$content,
    [VMware.Vim.View]$view_ref,
    [VMware.Vim]$obj_type,
    [array]$path_set,
    [bool]$incl_ref,
    [string]$key)
    if (!$path_set.Contains($key)) { throw "Key is not one of the paths in path_set." }
    
    $collector = $content

}

if ($input.Length -eq 0) {$input = $VMHost}

$input | % {
  $vmhostview = VMware.VimAutomation.Core\Get-View $_.ID
  $esxname = $vmhostview.Name
  $nsview = VMware.VimAutomation.Core\Get-View $vmhostview.ConfigManager.NetworkSystem

  foreach ($physnic in $nsview.NetworkInfo.Pnic) {
    $DevId = $null
    $Address = $null
    $PortId = $null
    $vLan = $null
    $LinkSpeed_Mb = $physnic.LinkSpeed.SpeedMb

    $pnicInfo = $nsview.QueryNetworkHint($physnic.Device)
    foreach ( $hint in $pnicInfo ) {
      $csp = $hint.ConnectedSwitchPort
      if ($csp) {
        $DevId = $csp.DevId
        $Address = $csp.Address
        $PortId = $csp.PortId
        $vLan = $csp.vLan
      }
      $csp = $null
    }
    [PSCustomObject]@{
        VMHost = $esxname;
        VMNic = $physnic.Device;
        LinkSpeed_Mb = $LinkSpeed_Mb;
        DevId = $DevId;
        Address = $Address;
        PortId = $PortId;
        vLan = $vLan
    }
  }
} | sort -Property VMHost,VMNic | ft -a

Get-CDP.ps1

<#
.SYNOPSIS
Get CDP information from one or more ESX hosts.

.PARAMETER VMHost
VMHost can be a list of the below entries:
  - FQDN name of the host
  - VMware.Vim.HostSystem (return type of 'Get-View -ViewType HostSystem')
  - VMware.VimAutomation.ViCore.Impl.V1.Inventory.VMHostImpl (return type of 'Get-VMHost')

.INPUTS
One or more VMHost object can be piped to the script.

.OUTPUTS
If $VMHost is piped in, returns a PSCustomObject for each piece of CDP info.
If $VMHost is passed as a parameter, returns a single formated table with all the CDP info.

.EXAMPLE
Running directly the script. Connection information will be prompted when needed.
PS> .\Get-CDP.ps1

.EXAMPLE
Connect first to any VIServer and pipe the result returned from Get-VMHost.
PS> Connect-VIServer xxx -User xxx -Password xxx
PS> Get-VMHost -Name abc* | .\Get-CDP.ps1

.EXAMPLE
Piping host names to the script or passing them as parameter.
The first command with Sort-Object and Format-Table is equivalent to the second one.
PS> 'esx1.example.com','esx2.example.com' | .\Get-CDP.ps1 | Sort-Object -Property VMHost,VMNic | Format-Table -AutoSize
PS> .\Get-CDP.ps1 -VMHost 'esx1.example.com','esx2.example.com'
#>
param(
    [Parameter(ValueFromPipeline, Mandatory = $true)]
    [object[]]$VMHost
)

Begin {
    # make sure a VIServer is connected
    while ($null -eq $global:defaultviserver) {
        $viServer = Read-Host -Prompt "vCenter / ESXi host to connect to"
        Connect-VIServer -Server $viServer > $null
    }

    function getCdp {
        param ($hostObj)

        # check for invalid host object
        if ($null -eq $hostObj) {
            Write-Host ("Host object is null.")
            return
        }
        if ($hostObj -is [string]) {
            Write-Progress -Activity ("Host: " + $hostObj) -Status "Getting HostSystem object..."
            $vmhostview = Get-View -ViewType HostSystem -Filter @{"Name"=$hostObj} -Property "Name","ConfigManager.NetworkSystem"
        }
        if ($hostObj -is [VMware.VimAutomation.ViCore.Impl.V1.Inventory.VMHostImpl]) {
            Write-Progress -Activity ("Host: " + $hostObj.Name) -Status "Getting HostSystem object..."
            $vmhostview = Get-View -VIObject $hostObj -Property "Name","ConfigManager.NetworkSystem"
        }
        if (($null -eq $vmhostview) -or
            ($vmhostview -isnot [VMware.Vim.HostSystem])) {
            Write-Host ("Invalid host object " + $hostObj + ".")
            return
        }

        # get CDP info
        $esxname = $vmhostview.Name
        Write-Progress -Activity ("Host: " + $esxname) -Status "Getting CDP information..." -PercentComplete 0
        #Write-Host ("Getting CDP data from " + $esxname + "...")
        $nsview = Get-View $vmhostview.ConfigManager.NetworkSystem

        for ($i = 0; $i -lt $nsview.NetworkInfo.Pnic.Length; $i++) {#foreach ($physnic in $nsview.NetworkInfo.Pnic) {
            $physnic = $nsview.NetworkInfo.Pnic[$i]

            $DevId = $null
            $Address = $null
            $PortId = $null
            $vLan = $null
            $LinkSpeed_Mb = $physnic.LinkSpeed.SpeedMb

            $pnicInfo = $nsview.QueryNetworkHint($physnic.Device)
            foreach ( $hint in $pnicInfo ) {
                $csp = $hint.ConnectedSwitchPort
                if ($csp) {
                    $DevId = $csp.DevId
                    $Address = $csp.Address
                    $PortId = $csp.PortId
                    $vLan = $csp.vLan
                }
                $csp = $null
            }

            [PSCustomObject]@{
                VMHost       = $esxname;
                VMNic        = $physnic.Device;
                LinkSpeed_Mb = $LinkSpeed_Mb;
                DevId        = $DevId;
                Address      = $Address;
                PortId       = $PortId;
                vLan         = $vLan
            } | Write-Output

            Write-Progress -Activity ("Host: " + $esxname) -Status "Getting CDP information..." -PercentComplete (($i+1) / $nsview.NetworkInfo.Pnic.Length * 100)
        }
    }
}

Process {
    # when piped, $_ != $null and $_ == $VMHost[0]; $VMHost is an array with 1 element.
    # when run directly, $_ == $null; $VMHost is an array with all elements.
    if ($MyInvocation.ExpectingInput) {
        # pass the cdp object directly when in a pipeline
        getCdp $_
    }
    else { # direct parameter
        $VMHost | ForEach-Object {
            getCdp $_
        } | Sort-Object -Property VMHost,VMNic | Format-Table -AutoSize
    }
}

End {

}

List-Host.ps1

# param(
#     [Parameter(ValueFromPipeline, Mandatory = $true)]
#     [object[]]$VMHost
# )

# make sure a VIServer is connected
while ($null -eq $global:DefaultVIServer) {
    $viStr = Read-Host -Prompt "vCenter / ESXi host to connect to"
    Connect-VIServer -Server $viStr > $null
}

# run on default servers
$view = Get-View -ViewType HostSystem -Property 'Name',
                                                'Summary.OverallStatus',
                                                'Summary.Runtime.PowerState',
                                                'Summary.QuickStats.Uptime',
                                                'Summary.QuickStats.OverallCpuUsage',
                                                'Summary.QuickStats.OverallMemoryUsage',
                                                'Summary.Hardware.CpuMhz',
                                                'Summary.Hardware.NumCpuCores',
                                                'Summary.Hardware.MemorySize',
                                                'Summary.Hardware.OtherIdentifyingInfo'

$view | Sort-Object -Property 'Name' | Format-Table -Property 'Name',
    @{label='Status';           e={ $_.Summary.OverallStatus }},
    @{label='PowerState';       e={ $_.Summary.Runtime.PowerState }},
    @{label='Up Time';          e={ '{0:0.#} days' -f ($_.Summary.QuickStats.Uptime / 86400) }},
    @{label='CPU Usage';        e={ if (($_.Summary.QuickStats.OverallCpuUsage, $_.Summary.Hardware.CpuMhz, $_.Summary.Hardware.NumCpuCores).Contains($null))
                                        {'unknown'}
                                    else
                                        { '{0:f0}%' -f ($_.Summary.QuickStats.OverallCpuUsage / $_.Summary.Hardware.CpuMhz / $_.Summary.Hardware.NumCpuCores * 100) }}},
    @{label='Memory Usage';     e={ if (($_.Summary.QuickStats.OverallMemoryUsage, $_.Summary.Hardware.MemorySize).Contains($null))
                                        {'unknown'}
                                    else
                                        { '{0:f0}%' -f ($_.Summary.QuickStats.OverallMemoryUsage / $_.Summary.Hardware.MemorySize * 104857600) }}},
    @{label='Service Tag';       e={ $_.Summary.Hardware.OtherIdentifyingInfo[1].IdentifierValue }}