In the Connection Monitoring tab, you can:
Automatically detect loss of connectivity to the default gateway - Select this option to detect connectivity loss by sending ARP requests (pinging) to the default gateway and expecting responses.
Note - If you use Dynamic Routing, you must clear this box to prevent probing of the default gateway.
Monitor connection state by sending probe packets to one or more servers on the Internet - Select this option to detect connectivity loss by using more methods and servers.
Connection probing method - Select one of the options.
Ping addresses - When you select this option, you can configure up to three servers by IP address or host name.
Probe DNS servers - When you select this option, the appliance probes the DNS servers as defined in the Internet connection and expects responses.
For more information, see Configuring Internet Connectivity.