Forcing an interface connect after it has gone down

Hi, newbie here.

I have a couple of mini routers (GL-AR300M and GT-MT300N) that are mainly used for vpn connections, both using the latest 2.25 firmware. Occasionally the VPN server disconnects meaning that each time I need to restart the mini router or login and force a manual (re)connect.

Could somebody tell me if there is a way to force an interface reconnect if it should go down. E.g by using a tracking ip that you can see under the load balancing menu. E.g I would like to detect when the VPN connection has disconnected by issuing periodic tracking requests through it and then force it to restart.

thanks for any help.