I had so many times the problem where my VPS'es with my SER's are down and I have no clue about it. I got annoyed and started to look for a solution, which I found and want to share with you guys!
The process is simple and quick:
1) Register for free at http://uptimerobot.com
1.1) Add New Monitor
1.2) Select monitor type - Ping
1.3) Enter your VPS IP and point to your preferred email to receive notifications.
So now when ever your VPS will go offline you will receive an email with a notification.
Hope this will be useful for some of you!