It's much better to monitor that the server URL is responding as all the moving parts of the Tableau server have to be working to get a valid response from the URL. There are loads of web monitoring apps out there which allow you to monitor URLs in this way.
Got the 'Server is Running'. Had to mention the path where the tabadmin is located. What i need now is how to send an email when Server is not up and running.
Checkout febooti, a command-line emailer.
But we have the capability to send email on process failure. It seems like you're re-creating the wheel here:
Is there something you need that the built-in feature doesn't support?