Configuring static routes
The System > Network > Routing tab displays a list of routes and lets you configure static routes and gateways used by the FortiMail unit.
Static routes direct traffic exiting the FortiMail unit. You can specify through which network interface a packet will leave, and the IP address of a next-hop router that is reachable from that network interface. The router is aware of which IP addresses are reachable through various network pathways, and can forward those packets along pathways capable of reaching the packets’ ultimate destinations.
A default route is a special type of static route. A default route matches all packets, and defines a gateway router that can receive and route packets if no other, more specific static route is defined for the packet’s destination IP address.
You should configure at least one static route, a default route, that points to your gateway. However, you may configure multiple static routes if you have multiple gateway routers, each of which should receive packets destined for a different subset of IP addresses.
To determine which route a packet will be subject to, the FortiMail unit compares the packet’s destination IP address to those of the static routes and forward the packet to the route with the largest prefix match.
For example, if an SMTP server is directly attached to one of the network interfaces, but all other destinations, such as connecting clients, are located on distant networks such as the Internet, you might need to add only one route: a default route for the gateway router through which the FortiMail unit connects to the Internet.
When you add a static route through the web UI, the FortiMail unit evaluates the route to determine if it represents a different route compared to any other route already present in the list of static routes. If no route having the same destination exists in the list of static routes, the FortiMail unit adds the static route.
To access this part of the web UI, your administrator account’s:
• Domain must be System
• access profile must have Read-Write permission to the Others category
To configure static routes
1. Go to System > Network > Routing.
2. Either click New to add a route or double-click a route to modify it.
A dialog appears.
3. In Destination IP/netmask, enter the destination IP address and netmask of packets that will be subject to this static route.
To create a default route that will match all packets, enter 0.0.0.0/0.0.0.0.
4. Select the interface that this route applies to.
5. In Gateway, type the IP address of the next-hop router to which the FortiMail unit will forward packets subject to this static route. This router must know how to route packets to the destination IP addresses that you have specified in Destination IP/netmask. For an Internet connection, the next hop routing gateway routes traffic to the Internet.
6. Click Create.