Quick and Dirty: Space Reclaimation using PowerCLI and VAAI Storage

Today we have another small script from the Quick and Dirty series. If you use VAAI-compatible storage and provision VMs thinly, you have to perform a space reclaim from time to time to be able to use the deleted VMFS blocks again.

In the VMware Knowledge Base ist das Vorgehen mittels „esxcli“ beschrieben, ich finde den Weg über die PowerCLI aber etwas angenehmer und habe daher eine kleine Text-GUI hinzugefügt:

So muss nur das Script aus der PowerCLI gestartet werden und dann lassen sich bequem die Datastore auswählen auf dem das „UNMAP“ Kommando ausgeführt werden soll.

The script works with the PowerCLI 6 and the EMC XtremIO and probably also with other VAAI compatible storage. The reclaim unit size can be adjusted in line 8. (Default is 200 for 1 MB blocks for VMFS3/5).

Here is the script:

function Reclaim-UnusedDatastoreSpace ($datastore, $ESXiHost)
{
    try 
		{
		write-host "Datastore Name: $datastore"
		write-host "ESX Server: $ESXiHost"
        $ESXCLI = Get-EsxCli -VMHost $ESXiHost
		$RETVAL = $ESXCLI.storage.vmfs.unmap(200, $datastore, $null)
        }
    catch [VMware.VimAutomation.Sdk.Types.V1.ErrorHandling.VimException.ViError]
		{
			
        }
}

$settimeout = Set-PowerCLIConfiguration -WebOperationTimeoutSeconds -1 -Scope Session -Confirm:$false

clear-host
write-host ""
$vcenter = read-host "Enter vCenter Name"

try
	{
		$connect = connect-viserver $vcenter
	}
catch
	{
		write-host "Can't connect vCenter"
		exit 0
	}
do
{
$clusterlist = get-cluster
$clusternumber = 1
$selectcluster = @()
foreach ($cluster in $clusterlist)
	{
		$clustername = $cluster.name
		$selectcluster += new-object PSObject -property @{Number="$Clusternumber";Clustername="$Clustername"}
		$clusternumber++
	}

$selectcluster | ft number,clustername -autosize
	
$selectedclusternumber = read-host "Select Cluster (Enter Number)"
try
	{
		$selectedclustername = ($selectcluster | where {$_.Number -eq $selectedclusternumber} | select Clustername).Clustername
		$esxhost = get-cluster $selectedclustername | get-vmhost | select -first 1
	}
catch
	{
		write-host "Can't get ESX Server"
	}
	
$datastorelist = get-vmhost $esxhost | get-datastore
$datastorenumber = 1
$selectdatastore = @()
foreach ($datastore in $datastorelist)
	{
		$datastorename = $datastore.name
		$selectdatastore += new-object PSObject -property @{Number="$Datastorenumber";DatastoreName="$datastorename"}
		$datastorenumber++
	}
	
$selectdatastore | ft Number,DatastoreName -autosize

$selecteddatastorenumber = read-host "Select Datastore (Enter Number)"
try
	{
		$selecteddatastorename = ($selectdatastore | where {$_.Number -eq $selecteddatastorenumber}).datastorename
		write-host ""
		write-host "Working..."
		write-host ""
		Reclaim-UnusedDatastoreSpace $selecteddatastorename $esxhost
		write-host ""
		write-host "Finished" -foregroundcolor green
		write-host ""
		$newrun = read-host "New run? (Yes/No)"
	}
catch
	{
		write-host "Can't reclaim Space"
	}	
}
while ($newrun -match "Yes" -or $newrun -match "y")