Reboot if OpenVPN not working (Newbie)

I’ve been trying to setup ubuntu as a torrent box. Using Vuze I’ve set it to bind to my VPN interface but it doesnt work. It will download wheather or not the interface is connected.

So, Im taking a different approach. I want a command written that will reboot if it’s not connected to the VPN. I use Openvpn, set to autoconnect on boot.
If the connection is lost to the VPN, and It can only access the regualar (Non-VPNed) ethernet, I want it to reboot. I do not want any connection happening unless the VPN is connected.

Im new to linux so detailed instructions would be appreciated.

PS. Here is a link to my orgional question about Vuze’s bind option not working; Vuze Binding with VPN’s network adapter
In case someone has some new input for me. The command for rebooting would still be appreciated as when I do lose connection to VPN it would be nice to have everything automatically restarted.