PRTGNetScaler.ps1

try
{
$ReadOnlyUser = "Read Only Username"
$EncryptedPassword = "Encrypted Password"

#Decrypt the password for use in the script
$SecurePassword = $EncryptedPassword | ConvertTo-SecureString
$Marshal = [System.Runtime.InteropServices.Marshal]
$Bstr = $Marshal::SecureStringToBSTR($SecurePassword)
$Password = $Marshal::PtrToStringAuto($Bstr)
$Marshal::ZeroFreeBSTR($Bstr)

# Disable SSL certificate checking so we can connect to servers using a cert signed by a private CA and enable TLS1.2
[System.Net.ServicePointManager]::ServerCertificateValidationCallback = {$true}
[Net.ServicePointManager]::SecurityProtocol = [Net.SecurityProtocolType]::Tls12

#Grab the Host IP/FQDN from the Device Config in PRTG
$TargetHost = $env:prtg_host

#Send our request and convert the result into a JSON object
$NetScalerQuery = @{uri = "https://$TargetHost/nitro/v1/config/lbvserver";
                    Method = 'GET';
                    Headers = @{'X-NITRO-USER' = '$ReadOnlyUser'; 'X-NITRO-PASS' = '$Password';}
                    }
$NetScalerQueryResult = Invoke-WebRequest @NetScalerQuery -UseBasicParsing
$NetScalerQueryJSON = ConvertFrom-Json -InputObject $NetScalerQueryResult

#Count the number of Virtual Servers returned
$LBServerTotal = $NetScalerQueryJSON.lbvserver.count


$MessageText = "OK"
Write-Host "<prtg>"

#Loop through the Virtual Servers, evaluate their state and output for PRTG
For ($LBServerCount=0; $LBServerCount -lt $LBServerTotal; $LBServerCount++){
        $ChannelName = $NetScalerQueryJSON.lbvserver[$LBServerCount].name
        $CurrentState = $NetScalerQueryJSON.lbvserver[$LBServerCount].curstate
        $EffectiveState = $NetScalerQueryJSON.lbvserver[$LBServerCount].effectivestate
        $Health = $NetScalerQueryJSON.lbvserver[$LBServerCount].health
            If ($CurrentState -eq "DOWN" -or $EffectiveState -eq "DOWN" -or $Health -ne "100") {
                    $StateValue = 1
                        If ($MessageText -eq "OK") {
                                $MessageText = $ChannelName
                                }
                                Else {
                                $MessageText = $MessageText + " " + $ChannelName
                                }
                    }
                    Else {
                    $StateValue = 0
                    }
        Write-Host "<result>"
                   "<channel>$ChannelName</channel>"
                   "<value>$StateValue</value>"
                   "<showChart>1</showChart>"
                   "<showTable>1</showTable>"
		   "<LimitMaxError>0</LimitMaxError>"
                   "<LimitMode>1</LimitMode>"
                   "</result>"
                   }
Write-Host "<Text>$MessageText</Text>"
Write-Host "</prtg>"
}
#If try code block fails then throw an error to PRTG
catch
{
    Write-Host "<prtg>"
    Write-host "<error>1</error>"
    Write-Host "<text>Sensor Error</text>"
    Write-Host "</prtg>"
}