System Settings : Network : Static routes : Add a static route
 
Add a static route
Go to System Settings > Network, select the Routing Table button, and select Create New to add a route, or select the route number to edit an existing route.
Figure 60: Create new route
Configure the following settings, then select OK to create the new static route:
Destination IP/Mask
Enter the destination IP address and netmask for this route.
Gateway
Enter the IP address of the next hop router to which this route directs traffic.
Interface
Select the network interface that connects to the gateway.