VMware: vFRC Management with GUI PowerCLI

After Automating vFRC deployment with PowerCLI let's have a step further by creating a PowerCLI script that allow administrators to manage vFRC using a Graphical User Interface (GUI).

I created this PowerCLI GUI vFRC management tool as a sample that can be used as a starting point for developing your own GUIs. What's this tool for? It simply gives you the ability to change Cache Size and Block Size of a VM disk on a vFRC enabled host.

PowerCLI GUIs, even if it would be more appropriate saying PowerShell, are very similar to .NET ones. Features, capabilities and results are quite the same since they use the common framework Microsoft provides for building frames and controls such as buttons, textboxes, labels, comboboxes, etc.

Code it's quite commented itself, I divided the script in two macro-areas: the function area, where logic is done, and a "design area" where I essentially defined all elements composing the user interface, their size, their position, what action to trigger in case of user intervention, etc.

I think it is important to spend a few words on elements positioning into the form.

An element position can be defined in several ways. In this script I used both the "compact" and the "extended" synthax.

The extended way to define an element position is:

$Component.Left=10
$Component.Top=20
$Component.Right=30
$Component.Bottom=40

While the compact way:

$Component.Location = New-Object System.Drawing.Size(10,20,30,40)
Numeric values in code snippets above are distances, measured in pixels, that the defined component has from the border of the containing element.
Let's be more clear! If a button is contained in a form and this button has: New-Object System.Drawing.Size(10,20) this indicates that button is located 10px from the left border of the form and 20px from the upper border of the form.
The positioning is relative to the containing element though, because if the same button is contained in a GroupBox which itself is contained in a form, the above 10px from left border and 20px from upper border this time are referred to GroupBox borders and not to the form ones.

Let's now have a look on how vFRC GUI management tool works.

As usual for running PowerCLI script save the code with ".ps1" extension then run it from PowerCLI console.

Here's the code for vFRC GUI management tool, I've also pushed it to GitHub, you can find it here:

vFRC GUI on GitHub

 
##################BEGIN FUNCTIONS


function connectServer{

    try {

    $connect = Connect-VIServer -Server $serverTextBox.Text -User $usernameTextBox.Text -Password $passwordTextBox.Text

    $buttonConnect.Enabled = $false #Disable controls once connected
    $serverTextBox.Enabled = $false
    $usernameTextBox.Enabled = $false
    $passwordTextBox.Enabled = $false
    $buttonDisconnect.Enabled = $true #Enable Disconnect button

    getVmHosts #Populate DropDown list with all hosts connected (if vCenter)

    $HostDropDownBox.Enabled=$true
    
    
    $outputTextBox.text = "`nCurrently connected to $($serverTextBox.Text)" #If connection is successfull let user know it

    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong!!"
    
    }

}

function disconnectServer{

    try {

    $disconnect = Disconnect-VIServer -Confirm:$false -Force:$true

    $buttonConnect.Enabled = $true #Enable login controls once disconnected
    $serverTextBox.Enabled = $true
    $usernameTextBox.Enabled = $true
    $passwordTextBox.Enabled = $true
    $buttonDisconnect.Enabled = $false #Disable Disconnect button
    
    $HostDropDownBox.Items.Clear() #Remove all items from DropDown boxes
    $HostDropDownBox.Enabled=$false #Disable DropDown boxes since they are empty
    $VmDropDownBox.Items.Clear()
    $VmDropDownBox.Enabled=$false
    $HardDiskDropDownBox.Items.Clear()
    $HardDiskDropDownBox.Enabled=$false
    $cacheBlockSizeKBTextBox.Enabled=$false
    $cacheSizeGBTextBox.Enabled=$false
    
    $outputTextBox.text = "`nSuccessfully disconnected from $($serverTextBox.Text)" #If disconnection is successfull let user know it

    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong!!"
    
    }

}

function getPoweredOffVms{

    try {
    
    $poweredoffvms = Get-VM | Select-Object Name, VMHost, PowerState, Version | Where-Object {$_.PowerState -eq "PoweredOff" -and $_.Version -eq "v10" -and $_.VMHost -eq $(Get-VMHost | Where-Object {$_.Name -eq $HostDropDownBox.SelectedItem.ToString()})} #Returns only powered Off VMs that are hardware v10 (since older hw versions are not supported)

        foreach ($vm in $poweredoffvms) {
            $VmDropDownBox.Items.Add($vm.Name) #Add VMs to DropDown List
        }

    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong!!"
    
    }


}

function getVmHosts{

    try {

    $vmhosts = Get-VMHost | Where-Object {$_.PowerState -eq "PoweredOn" -and $_.ConnectionState -eq "Connected"} #Returns only powered On VmHosts

        foreach ($vm in $vmhosts) {
            $HostDropDownBox.Items.Add($vm.Name) #Add Hosts to DropDown List
        }    

    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong getting VMHosts!!"
    
    }

}

function getVmHostvFlashResource{

    try {
    
    $outputTextBox.text = "`nGetting vFRC configuration for VMHost: $($HostDropDownBox.SelectedItem.ToString())"
    
    $vFlashConfig = Get-VMHostVFlashConfiguration -VMHost $HostDropDownBox.SelectedItem.ToString()
    $capacityGbTextBox.text = $($vFlashConfig.CapacityGB)
    $swapCacheGbTextBox.text = $($vFlashConfig.SwapCacheReservationGB)
    $extentsTextBox.text = $($vFlashConfig.Extents)
    
    getPoweredOffVms #Populate DropDown list with all powered off VMs 

    $VmDropDownBox.Enabled=$true

    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong getting VMHostsvFlashResource!!"
    
    }

}

function getVmvFlashResource{

    try {
    
    $outputTextBox.text = "`nGetting vFRC configuration for VM: $($VmDropDownBox.SelectedItem.ToString())"
    
    $vFlashConfig = Get-HardDiskVFlashConfiguration -HardDisk $(Get-HardDisk -VM $VmDropDownBox.SelectedItem.ToString() -Name $HardDiskDropDownBox.SelectedItem.ToString())
        
    $cacheBlockSizeKBTextBox.text = $vFlashConfig.CacheBlockSizeKB
    
    $cacheSizeGBTextBox.text = $vFlashConfig.CacheSizeGB        
    
    $buttonSetvFrcVm.Enabled = $true #Enable vFRC related button/texbox
    $cacheBlockSizeKBTextBox.Enabled=$true
    $cacheSizeGBTextBox.Enabled=$true
    
    }

    catch {
    
    $outputTextBox.text = "`nSomething went wrong getting VMvFlashResource!!"
    
    }

}

function setVmvFlashResource{
    try{
    
    $cacheSizeGB = $cacheSizeGBTextBox.Text -as [int] #Convert values to integer
    $capacityGb = $capacityGbTextBox.Text -as [int]
    $swapCacheGb = $swapCacheGbTextBox.Text -as [int]
    
    
    if((($cacheBlockSizeKBTextBox.Text -eq 4) -or ($cacheBlockSizeKBTextBox.Text -eq 8) -or ($cacheBlockSizeKBTextBox.Text -eq 16) -or ($cacheBlockSizeKBTextBox.Text -eq 32) -or ($cacheBlockSizeKBTextBox.Text -eq 64) -or ($cacheBlockSizeKBTextBox.Text -eq 128) -or ($cacheBlockSizeKBTextBox.Text -eq 256) -or ($cacheBlockSizeKBTextBox.Text -eq 512) -or ($cacheBlockSizeKBTextBox.Text -eq 1024))){ #Control if CacheBlockSize value is allowed
 
        if($cacheSizeGB -le ($capacityGb - $swapCacheGb)){ #Control if enough resources are available
        
        Set-HardDiskVFlashConfiguration -VFlashConfiguration (Get-HardDiskVFlashConfiguration -HardDisk $(Get-HardDisk -VM $VmDropDownBox.SelectedItem.ToString() -Name $HardDiskDropDownBox.SelectedItem.ToString())) -CacheSizeGB $cacheSizeGBTextBox.Text -CacheBlockSizeKB $cacheBlockSizeKBTextBox.Text -Confirm:$false
        
        getVmvFlashResource #Display updated values
        
        $outputTextBox.text = "`nvFRC correctly set for VM $($VmDropDownBox.SelectedItem.ToString())"
        
        }
        
        else{
        
        $outputTextBox.text = "`nNot enough resources available!!"
        
        }
        
    }
    else{
    
    $outputTextBox.text = "`nvFRC -Block Size in KB- accepted values are: 4, 8, 16, 32, 64, 128, 256, 512, 1024"
    
    }    
    
    }
    catch{
    
    $outputTextBox.text = "`nSomething went wrong setting VMvFlashResource!!"
    
    }
}

function getDisks{

    try {
    
    $HardDiskDropDownBox.Items.Clear() #Remove all items from DropDown List since it may be dirtied by previous executions
    
    $harddisks = Get-HardDisk -VM $VmDropDownBox.SelectedItem.ToString()
    
        foreach ($disk in $harddisks) {
            $HardDiskDropDownBox.Items.Add($disk.Name) #Add Hosts to DropDown List
        }
        
    $HardDiskDropDownBox.Enabled = $true #Enable dropdownbox
        
    }
    catch{
       $outputTextBox.text = "`nSomething went wrong getting VmHardDisks!!"
    }
}

##################END FUNCTIONS

Import-Module VMware.VimAutomation.Extensions #Import VSAN & vFRC cmdlets

[void] [System.Reflection.Assembly]::LoadWithPartialName("System.Drawing") 
[void] [System.Reflection.Assembly]::LoadWithPartialName("System.Windows.Forms") 

##################Main Form Definition
    
    $main_form = New-Object System.Windows.Forms.Form 
    $main_form.Text = "vFRC GUI" #Form Title
    $main_form.Size = New-Object System.Drawing.Size(500,630) 
    $main_form.StartPosition = "CenterScreen"

    $main_form.KeyPreview = $True
    #$main_form.Add_KeyDown({if ($_.KeyCode -eq "Enter") 
    #{$x=$ServerTextBox.Text;$main_form.Close()}})
    $main_form.Add_KeyDown({if ($_.KeyCode -eq "Escape") 
    {$main_form.Close()}})

##################GroupBox Definition

    $groupBox1 = New-Object System.Windows.Forms.GroupBox
    $groupBox1.Location = New-Object System.Drawing.Size(10,5) 
    $groupBox1.size = New-Object System.Drawing.Size(190,200) #Width, Heigth
    $groupBox1.text = "Connect to vCenter or ESXi host:" 
    $main_form.Controls.Add($groupBox1) 

    $groupBox2 = New-Object System.Windows.Forms.GroupBox
    $groupBox2.Location = New-Object System.Drawing.Size(10,215) 
    $groupBox2.size = New-Object System.Drawing.Size(470,100) #Width, Heigth
    $groupBox2.text = "Hosts Operations:" 
    $main_form.Controls.Add($groupBox2) 

    $groupBox3 = New-Object System.Windows.Forms.GroupBox
    $groupBox3.Location = New-Object System.Drawing.Size(10,325) 
    $groupBox3.size = New-Object System.Drawing.Size(470,100) #Width, Heigth
    $groupBox3.text = "VMs Operations:" 
    $main_form.Controls.Add($groupBox3) 

    $groupBox4 = New-Object System.Windows.Forms.GroupBox
    $groupBox4.Location = New-Object System.Drawing.Size(10,435) 
    $groupBox4.size = New-Object System.Drawing.Size(470,150) #Width, Heigth
    $groupBox4.text = "Output:" 
    $main_form.Controls.Add($groupBox4)
    
    $groupBox5 = New-Object System.Windows.Forms.GroupBox
    $groupBox5.Location = New-Object System.Drawing.Size(210,5) 
    $groupBox5.size = New-Object System.Drawing.Size(270,200) #Width, Heigth
    $groupBox5.text = "Instructions:" 
    $main_form.Controls.Add($groupBox5)  

##################Label Definition

    $Label1 = New-Object System.Windows.Forms.Label
    $Label1.Location = New-Object System.Drawing.Point(10, 20)
    $Label1.Size = New-Object System.Drawing.Size(120, 14)
    $Label1.Text = “IP Address or FQDN:”
    $groupBox1.Controls.Add($Label1) #Member of GroupBox1

    $Label2 = New-Object System.Windows.Forms.Label
    $Label2.Location = New-Object System.Drawing.Point(10, 70)
    $Label2.Size = New-Object System.Drawing.Size(120, 14)
    $Label2.Text = "Username:”
    $groupBox1.Controls.Add($Label2) #Member of GroupBox1

    $Label3 = New-Object System.Windows.Forms.Label
    $Label3.Location = New-Object System.Drawing.Point(10, 120)
    $Label3.Size = New-Object System.Drawing.Size(120, 14)
    $Label3.Text = "Password:”
    $groupBox1.Controls.Add($Label3) #Member of GroupBox1
    
    $Label4 = New-Object System.Windows.Forms.Label
    $Label4.Location = New-Object System.Drawing.Point(10, 15)
    $Label4.Size = New-Object System.Drawing.Size(120, 14)
    $Label4.Text = “Select Host:”
    $groupBox2.Controls.Add($Label4) #Member of GroupBox2
    
    $Label5 = New-Object System.Windows.Forms.Label
    $Label5.Location = New-Object System.Drawing.Point(200, 55)
    $Label5.Size = New-Object System.Drawing.Size(90, 14)
    $Label5.Text = “Capacity in GB:”
    $groupBox2.Controls.Add($Label5) #Member of GroupBox2
    
    $Label6 = New-Object System.Windows.Forms.Label
    $Label6.Location = New-Object System.Drawing.Point(300, 55)
    $Label6.Size = New-Object System.Drawing.Size(160, 14)
    $Label6.Text = “Swap Cache reserved in GB:”
    $groupBox2.Controls.Add($Label6) #Member of GroupBox2
    
    $Label7 = New-Object System.Windows.Forms.Label
    $Label7.Location = New-Object System.Drawing.Point(10, 55)
    $Label7.Size = New-Object System.Drawing.Size(80, 14)
    $Label7.Text = “Extents:”
    $groupBox2.Controls.Add($Label7) #Member of GroupBox2
    
    $Label8 = New-Object System.Windows.Forms.Label
    $Label8.Location = New-Object System.Drawing.Point(10, 15)
    $Label8.Size = New-Object System.Drawing.Size(120, 14)
    $Label8.Text = “Select VM:”
    $groupBox3.Controls.Add($Label8) #Member of GroupBox3
    
    $Label9 = New-Object System.Windows.Forms.Label
    $Label9.Location = New-Object System.Drawing.Point(10, 55)
    $Label9.Size = New-Object System.Drawing.Size(90, 14)
    $Label9.Text = “Block Size in KB:”
    $groupBox3.Controls.Add($Label9) #Member of GroupBox3
    
    $Label10 = New-Object System.Windows.Forms.Label
    $Label10.Location = New-Object System.Drawing.Point(200, 55)
    $Label10.Size = New-Object System.Drawing.Size(160, 14)
    $Label10.Text = “Cache size in GB:”
    $groupBox3.Controls.Add($Label10) #Member of GroupBox3
    
    $Label11 = New-Object System.Windows.Forms.Label
    $Label11.Location = New-Object System.Drawing.Point(200, 15)
    $Label11.Size = New-Object System.Drawing.Size(80, 14)
    $Label11.Text = “Hard Disk:”
    $groupBox3.Controls.Add($Label11) #Member of GroupBox3
    
    $Label12 = New-Object System.Windows.Forms.Label
    $Label12.Location = New-Object System.Drawing.Point(10, 15)
    $Label12.Size = New-Object System.Drawing.Size(250, 180)
    $Label12.Text = “1)Connect to vCenter or ESXi host `r`n`r`n2)Select host and get vFRC configuration `r`n`r`n3)Select VM `r`n`r`n4)Select VM Hard Disk to which enable vFRC `r`n`r`n5)Change -Block Size- and -Cache Size- to desired values `r`n`r`n6)Apply changes pressing -Set vFRC- button `r`n`r`n`Developed by @HostileCoding”
    $groupBox5.Controls.Add($Label12) #Member of GroupBox3

##################Button Definition

    $buttonConnect = New-Object System.Windows.Forms.Button
    $buttonConnect.add_click({connectServer})
    $buttonConnect.Text = "Connect"
    $buttonConnect.Top=170
    $buttonConnect.Left=10
    $groupBox1.Controls.Add($buttonConnect) #Member of GroupBox1

    $buttonDisconnect = New-Object System.Windows.Forms.Button
    $buttonDisconnect.add_click({disconnectServer})
    $buttonDisconnect.Text = "Disconnect"
    $buttonDisconnect.Top=170
    $buttonDisconnect.Left=100
    $buttonDisconnect.Enabled = $false #Disabled by default
    $groupBox1.Controls.Add($buttonDisconnect) #Member of GroupBox1

    $buttonvFrcHost = New-Object System.Windows.Forms.Button
    $buttonvFrcHost.Size = New-Object System.Drawing.Size(260,25) 
    $buttonvFrcHost.add_click({getVmHostvFlashResource})
    $buttonvFrcHost.Text = "Get vFRC configuration for selected Host"
    $buttonvFrcHost.Left=200
    $buttonvFrcHost.Top=25
    $groupBox2.Controls.Add($buttonvFrcHost) #Member of GroupBox2
    
    $buttonGetvFrcVm = New-Object System.Windows.Forms.Button
    $buttonGetvFrcVm.Size = New-Object System.Drawing.Size(125,25) 
    $buttonGetvFrcVm.add_click({getVmvFlashResource})
    $buttonGetvFrcVm.Text = "Get VM vFRC"
    $buttonGetvFrcVm.Left=335
    $buttonGetvFrcVm.Top=25
    $buttonGetvFrcVm.Enabled = $false #Disabled by default
    $groupBox3.Controls.Add($buttonGetvFrcVm) #Member of GroupBox3
    
    $buttonSetvFrcVm = New-Object System.Windows.Forms.Button
    $buttonSetvFrcVm.Size = New-Object System.Drawing.Size(125,25) 
    $buttonSetvFrcVm.add_click({setVmvFlashResource})
    $buttonSetvFrcVm.Text = "Set VM vFRC"
    $buttonSetvFrcVm.Left=335
    $buttonSetvFrcVm.Top=65
    $buttonSetvFrcVm.Enabled = $false #Disabled by default
    $groupBox3.Controls.Add($buttonSetvFrcVm) #Member of GroupBox3

##################TextBox Definition

    $serverTextBox = New-Object System.Windows.Forms.TextBox 
    $serverTextBox.Location = New-Object System.Drawing.Size(10,40) #Left, Top, Right, Bottom
    $serverTextBox.Size = New-Object System.Drawing.Size(165,20) 
    $groupBox1.Controls.Add($serverTextBox) #Member of GroupBox1

    $usernameTextBox = New-Object System.Windows.Forms.TextBox 
    $usernameTextBox.Location = New-Object System.Drawing.Size(10,90)
    $usernameTextBox.Size = New-Object System.Drawing.Size(165,20) 
    $groupBox1.Controls.Add($usernameTextBox) #Member of GroupBox1

    $passwordTextBox = New-Object System.Windows.Forms.MaskedTextBox #Password TextBox
    $passwordTextBox.PasswordChar = '*'
    $passwordTextBox.Location = New-Object System.Drawing.Size(10,140)
    $passwordTextBox.Size = New-Object System.Drawing.Size(165,20)
    $groupBox1.Controls.Add($passwordTextBox) #Member of GroupBox1
    
    $capacityGbTextBox = New-Object System.Windows.Forms.TextBox
    $capacityGbTextBox.Location = New-Object System.Drawing.Size(200,70)
    $capacityGbTextBox.Size = New-Object System.Drawing.Size(90,20)
    $capacityGbTextBox.Enabled=$false 
    $groupBox2.Controls.Add($capacityGbTextBox) #Member of GroupBox2
    
    $swapCacheGbTextBox = New-Object System.Windows.Forms.TextBox
    $swapCacheGbTextBox.Location = New-Object System.Drawing.Size(300,70)
    $swapCacheGbTextBox.Size = New-Object System.Drawing.Size(160,20)
    $swapCacheGbTextBox.Enabled=$false 
    $groupBox2.Controls.Add($swapCacheGbTextBox) #Member of GroupBox2
    
    $extentsTextBox = New-Object System.Windows.Forms.TextBox
    $extentsTextBox.Location = New-Object System.Drawing.Size(10,70)
    $extentsTextBox.Size = New-Object System.Drawing.Size(180,20)
    $extentsTextBox.Enabled=$false 
    $groupBox2.Controls.Add($extentsTextBox) #Member of GroupBox2
    
    $cacheBlockSizeKBTextBox = New-Object System.Windows.Forms.TextBox
    $cacheBlockSizeKBTextBox.Location = New-Object System.Drawing.Size(10,70)
    $cacheBlockSizeKBTextBox.Size = New-Object System.Drawing.Size(90,20)
    $cacheBlockSizeKBTextBox.Enabled=$false 
    $groupBox3.Controls.Add($cacheBlockSizeKBTextBox) #Member of GroupBox3
    
    $cacheSizeGBTextBox = New-Object System.Windows.Forms.TextBox
    $cacheSizeGBTextBox.Location = New-Object System.Drawing.Size(200,70)
    $cacheSizeGBTextBox.Size = New-Object System.Drawing.Size(125,20)
    $cacheSizeGBTextBox.Enabled=$false 
    $groupBox3.Controls.Add($cacheSizeGBTextBox) #Member of GroupBox3

    $outputTextBox = New-Object System.Windows.Forms.TextBox 
    $outputTextBox.Location = New-Object System.Drawing.Size(10,20)
    $outputTextBox.Size = New-Object System.Drawing.Size(450,120)
    $outputTextBox.MultiLine = $True 
    $outputTextBox.ReadOnly = $True
    $outputTextBox.ScrollBars = "Vertical"  
    $groupBox4.Controls.Add($outputTextBox) #Member of groupBox4

##################DropDownBox Definition

    $VmDropDownBox = New-Object System.Windows.Forms.ComboBox
    $VmDropDownBox.DropDownStyle = [System.Windows.Forms.ComboBoxStyle]::DropDownList #Disable user input in ComboBox
    $VmDropDownBox.Location = New-Object System.Drawing.Size(10,30) 
    $VmDropDownBox.Size = New-Object System.Drawing.Size(180,20) 
    $VmDropDownBox.DropDownHeight = 200
    $VmDropDownBox.Enabled=$false 
    $groupBox3.Controls.Add($VmDropDownBox)
    
    $handler_VmDropDownBox_SelectedIndexChanged={ #DropDownBox SelectedIndexChanged Handler
        try{
            if ($VmDropDownBox.Text.Length -gt 0) {
               getDisks 
            }
        }catch{
        }
    }
    $VmDropDownBox.add_SelectedIndexChanged($handler_VmDropDownBox_SelectedIndexChanged)

    $HostDropDownBox = New-Object System.Windows.Forms.ComboBox
    $HostDropDownBox.DropDownStyle = [System.Windows.Forms.ComboBoxStyle]::DropDownList #Disable user input in ComboBox
    $HostDropDownBox.Location = New-Object System.Drawing.Size(10,30) 
    $HostDropDownBox.Size = New-Object System.Drawing.Size(180,20) 
    $HostDropDownBox.DropDownHeight = 200
    $HostDropDownBox.Enabled=$false 
    $groupBox2.Controls.Add($HostDropDownBox)
    
    $HardDiskDropDownBox = New-Object System.Windows.Forms.ComboBox
    $HardDiskDropDownBox.DropDownStyle = [System.Windows.Forms.ComboBoxStyle]::DropDownList #Disable user input in ComboBox
    $HardDiskDropDownBox.Location = New-Object System.Drawing.Size(200,30) 
    $HardDiskDropDownBox.Size = New-Object System.Drawing.Size(125,20) 
    $HardDiskDropDownBox.DropDownHeight = 200
    $HardDiskDropDownBox.Enabled=$false 
    $groupBox3.Controls.Add($HardDiskDropDownBox)
    
    $handler_HardDiskDropDownBox_SelectedIndexChanged={ #DropDownBox SelectedIndexChanged Handler
        try{
            if ($HardDiskDropDownBox.Text.Length -gt 0) {
               $buttonGetvFrcVm.Enabled = $true #Enable button
            }
        }catch{
        }
    }
    $HardDiskDropDownBox.add_SelectedIndexChanged($handler_HardDiskDropDownBox_SelectedIndexChanged)

##################Show Form

    $main_form.Add_Shown({$main_form.Activate()})
    [void] $main_form.ShowDialog()

Once you launch it main form will pop-out:

Enter credentials of your vCenter Server or ESXi host and connect to it. If connected to a vCenter Server all powered on hosts connected to vCenter itself will be added to dropdown box. Select a vFRC-capable host and click Get vFRC configuration for selected Host.

Any powered off virtual machine with hardware version 10 (ESXi 5.5 VMs) residing on selected host will be listed. Select intended VM and the VM's hard disk on which you need to enable or change vFRC settings.

Press Get VM vFRC button to retrieve current vFRC informations for selected VM. Here you can change both Block Size in KB and Cache Size in GB for selected hard disk.

Once done press Set VM vFRC to apply changes.

When setting vFRC the tool checks whether Block Size is permitted (either 4,8,16,32,64,128,256,512 or 1024 KB) and if enough Cache Size is available (i.e. you cannot assign more cache that the available one).

That's all!!