Unable to return info on hosts in multiple clusters in PowerShell using PowerCLI

Question

I have a PowerShell script which is used to return information for each Host on a user specified cluster. The user provides the vCenter and cluster in as parameters and the script works as expected.

I am trying to modify this script so the user only needs to pass in the vCenter as a parameter and it would return information for all hosts on all clusters.

Here is the original script I have which works:

Param(
    $vc,
    $ClusterName
)

Add-PSSnapin VMware.VimAutomation.Core

Connect-VIServer $vc

$VMHosts = Get-Cluster $ClusterName | Get-VMHost  | ? { $_.ConnectionState -eq "Connected" } | Sort-Object -Property Name

foreach ($VMHost in $VMHosts) {

 Get-VMHostStorage -RescanAllHba -VMHost $VMHost | Out-Null
 $esx = Get-VMHost $VMHost
 foreach($hba in (Get-VMHostHba -VMHost $esx -Type "FibreChannel")){
     $target = ((Get-View $hba.VMhost).Config.StorageDevice.ScsiTopology.Adapter | where {$_.Adapter -eq $hba.Key}).Target
     $luns = Get-ScsiLun -Hba $hba  -LunType "disk"
     $nrPaths = ($target | %{$_.Lun.Count} | Measure-Object -Sum).Sum
     $deadPaths = $luns | Get-ScsiLunPath | Group-Object -Property state | ? { $_.Name -eq "Dead"}
     $hbaDevice = $hba.Device
     $targetCount = $target.Count
     $lunsCount = $luns.Count
     $deadPathCount = $deadPaths.Count

     "vmhost=$VMHost;hba=$hbaDevice;targets=$targetCount;devices=$lunsCount;paths=$nrPaths;deadpaths=$deadPathsCount|"

 }
}

Disconnect-VIServer -Confirm:$False

And here is my modified version:

Param(
    $vc
)

Add-PSSnapin VMware.VimAutomation.Core

Connect-VIServer $vc
$clusters = Get-Cluster

foreach ($cluster in $clusters) {

    $clusterName = $cluster.name
    $VMHosts = Get-Cluster $clusterName | Get-VMHost  | ? { $_.ConnectionState -eq "Connected" } | Sort-Object -Property Name


    foreach ($VMHost in $VMHosts) {


        Get-VMHostStorage -RescanAllHba -VMHost $VMHost | Out-Null
        $esx = Get-VMHost $VMHost

        foreach($hba in (Get-VMHostHba -VMHost $esx -Type "FibreChannel")){
            $target = ((Get-View $hba.VMhost).Config.StorageDevice.ScsiTopology.Adapter | where {$_.Adapter -eq $hba.Key}).Target
            $luns = Get-ScsiLun -Hba $hba  -LunType "disk"
            $nrPaths = ($target | %{$_.Lun.Count} | Measure-Object -Sum).Sum
            $deadPaths = $luns | Get-ScsiLunPath | Group-Object -Property state | ? { $_.Name -eq "Dead"}
            $hbaDevice = $hba.Device
            $targetCount = $target.Count
            $lunsCount = $luns.Count
            $deadPathCount = $deadPaths.Count
            "vmhost=$VMHost;hba=$hbaDevice;targets=$targetCount;devices=$lunsCount;paths=$nrPaths;deadpaths=$deadPathsCount|"
        }
    }
}



Disconnect-VIServer -Confirm:$False

The error that I am getting is:

Could not execute powershell command.
At \\xx\xxx\xxxx\scripts\vmwarePathCheckAllClusters.ps1:35 char:26
+         Get-VMHostStorage <<<<  -RescanAllHba -VMHost $VMHost | Out-Null

It seems that $VMHost is being return as null, but I can't work out why!

This is my first time using PowerCLI CommandLets and I am very new to PowerShell as well. I'm sure that this is something very simple and would appreciate any help. If you require anymore information I'll be more than happy to provide. BUMP!

EDIT: Here is the additional error info:

+         Get-VMHostStorage <<<<  -RescanAllHba -VMHost $VMHost | Out-Null ---> VMware.VimAutomation.Sdk.Types.V1.ErrorHandling.VimException.VimException: 9/24/2014 5:58:57 AM Get-VMHostStorage       Value cannot be found for the mandatory parameter VMHost     ---> System.Management.Automation.ParameterBindingException: Value cannot be found for the mandatory parameter VMHost

Answer 1

Have you tested running Get-VMHostStorage without -RescanAllHBA? Why do you think $VMHost is being returned as null? Maybe it finds the host, but nothing to rescan? Just a guess.

Not sure this could cause your problem, but you don't need to run Get-Cluster twice. Rather,

$VMHosts = $cluster | Get-VMHost  | ? <etc>

edit - For a given run of the script, how many times does the full error text appear? How many vmhosts were found in that run? Do you have a cluster without hosts? A host without storage? You could set $vmhost = $null or $cluster = $null if a value from one loop iteration seems to be corrupting the next iteration. (Sorry, there's gotta be a better way to phrase that... hopefully you catch my drift.) You could always put the offending line of code in a [try] block and handle the error with catch.

edit again - apparently this fixed it for the host in maintenance mode: if (!$VMHost) {continue}