Configuring routing
Traffic destined for the network behind the Cisco router must be routed to the GRE tunnel. To do this, create a static route
1. Go to Router > Static > Static Routes and select Create New.
For low-end FortiGate units, go to System > Network > Routing and select Create New.
2. Enter the following information and select OK.
Destination IP/Mask | Enter the IP address and netmask for the network behind the Cisco router. For example 10.21.101.0 255.255.255.0. |
Device | Select the GRE virtual interface. |
Distance (Advanced) | Leave setting at default value. |
In the CLI, using the example values, you would enter
config router static
edit 0
set device gre1
set dst 10.21.101.0 255.255.255.0
end