Perform IISReset in all the servers of a SharePoint Farm using PowerShell

clear
Remove-PSSnapin Microsoft.SharePoint.Powershell -ErrorAction SilentlyContinue
Add-PSSnapin Microsoft.SharePoint.Powershell

If ((Get-PSSnapIn -Name Microsoft.SharePoint.PowerShell -ErrorAction SilentlyContinue) -eq $null )  
{ Add-PSSnapIn -Name Microsoft.SharePoint.PowerShell } 
 
$host.Runspace.ThreadOptions = "ReuseThread" 
 
#Definition of the funcion that performs the IIS RESET in all the servers 
function PerformIISReset 
{     
    try 
    {         
        #Getting the servers where the IISReset is going to be done 
        $spServers= Get-SPServer | ? {$_.Role -eq "Application"} 
        foreach ($spServer in $spServers) 
        {             
            Write-Host "Perform IIS Reset in server $spServer" -f blue 
            iisreset $spServer /noforce "\\"$_.Address 
            iisreset $spServer /status "\\"$_.Address 
        }         
        Write-Host "IIS Reset completed successfully!!" -f blue   
    } 
    catch [System.Exception] 
    { 
        write-host -f red $_.Exception.ToString() 
    } 
} 
 
Start-SPAssignment –Global 
PerformIISReset 
Stop-SPAssignment –Global