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#                                                                                                              #
# PowerShell script to monitor the IIS process on all servers & send email alerts upon failure & success       #
# Last Revised By - Alex Alborzfard                                                                            #
# Last Revision Date - 05/20/09 			                                                       #	
# Input: A text file with the IP address of all servers in Princeton, one per line                             #
#                                                                                                              #
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# Define Global Variables
Param($list = $(Throw "List is required!"),$count=4,$email,[switch]$Verbose)


# Test WebDAV service function
function Test-WebDav ()
{
	param ( $Url = "$( throw 'URL parameter is required.')" )
	$xhttp = New-Object -ComObject msxml2.xmlhttp
	$xhttp.open("OPTIONS", $url, $false)
	$xhttp.send()
	if ( $xhttp.getResponseHeader("DAV") ) { $true }
	else { $false }
}


foreach ($Url in $MyListOfUrls) {
    if( test-webdav -url $url ) { DoStuffHere }
    else { ItBrokeDoSomethingElse }
}


# Send Email Function
function Send-Mail{
    Param($msg,$relay,$from,$to,$c,$cc,$subject,[switch]$html,$time)
    $SmtpClient = new-object system.net.mail.smtpClient 
    $MailMessage = New-Object system.net.mail.mailmessage 
    $SmtpClient.Host = $relay
    $mailmessage.from = $from 
    $mailmessage.To.add($to)
    if($cc) { foreach($c in $cc){$mailmessage.CC.add($c)} } 
    $mailmessage.Subject = $subject
    if($html)
    {
        $mailmessage.IsBodyHtml = 1 
        $mailmessage.Body = $msg
    }
    else
    {
        $mailmessage.Body = $msg
    }
    $smtpclient.Send($mailmessage)
}


# Check Process on Servers Function
function Check-Process {
   Param([string]$server)
      $ProcessItems = Get-WmiObject Win32_Process -namespace "root\cimv2" -computername $Server | where {$_.name -like "inetinfo.exe"}
   if($ProcessItems.statuscode -eq 0) {$true} else {$false}
}
if($Verbose){$VerbosePreference  = "Continue"}
$status = @{}
$time = Get-Date -format g
while($true)
{
    foreach($server in (get-Content $list))
    {
        $x = 0
        Write-Verbose "Processing Server $Server"
        for($i=0;$i -lt 4;$i++)
        {
            Write-Verbose "  Process Count $i"
            $result = Check-Process $Server
            if(!$result)
            {
                Write-Verbose '  Process Not Available Upping $x'
                $x++
                if($x -gt 3)
                {
                    if($status.$Server -ne "Down")
                    {
                        Write-Verbose "Setting Process Status to Down"
                        $Status.$Server = "Down"
                        Send-Mail -msg "Process IIS on Server $Server is down" -relay bb.pharmanet.com -from SrvrMonitor@pharmanet.com -to aalborzfard@pharmanet.com -subject "Process IIS on Server $Server is down at $time"
                    }
                }
            }
            else
            {
                if($status.$Server -ne "Up")
                {
                    Write-Verbose "Setting Process Status to Up"
                    $Status.$Server = "Up"
                    Send-Mail -msg "Process IIS on Server $Server is up" -relay bb.pharmanet.com -from SrvrMonitor@pharmanet.com -to aalborzfard@pharmanet.com -subject "Process IIS on Server $Server is up at $time"
                }
            }
        }
    }
    start-Sleep 60
}