Configuring A Default Route - Cisco 7604 Configuration Manual

Chapter 8 Configuring IP Routing and DHCP Services
Configuring Static and Default Routes
If you create a static route with an administrative distance greater than the administrative distance of the
Note
routing protocol running on the FWSM, then a route to the specified destination discovered by the
routing protocol takes precedence over the static route. The static route is used only if the dynamically
discovered route is removed from the routing table.
The following example creates a static route that sends all traffic destined for 10.1.1.0/24 to the router
(10.1.2.45) connected to the inside interface:
hostname(config)# route inside 10.1.1.0 255.255.255.0 10.1.2.45 1
You can define up to three equal cost routes to the same destination per interface. ECMP is not supported
across multiple interfaces. With ECMP, the traffic is not necessarily divided evenly between the routes;
traffic is distributed among the specified gateways based on an algorithm that hashes the source and
destination IP addresses.
The following example shows static routes that are equal cost routes that direct traffic to three different
gateways on the outside interface. The FWSM distributes the traffic among the specified gateways.
hostname(config)# route outside 10.10.10.0 255.255.255.0 192.168.1.1
hostname(config)# route outside 10.10.10.0 255.255.255.0 192.168.1.2
hostname(config)# route outside 10.10.10.0 255.255.255.0 192.168.1.3

Configuring a Default Route

A default route identifies the gateway IP address to which FWSM sends all IP packets for which it does
not have a learned or static route. A default route is simply a static route with 0.0.0.0/0 as the destination
IP address. Routes that identify a specific destination take precedence over the default route.
You can define up to three equal cost default route entries per device. Defining more than one equal cost
default route entry causes the traffic sent to the default route to be distributed among the specified
gateways. When defining more than one default route, you must specify the same interface for each
entry.
If you attempt to define more than three equal cost default routes, or if you attempt to define a default
route with a different interface than a previously defined default route, you receive the message
"ERROR: Cannot add route entry, possible conflict with existing routes."
To define the default route, enter the following command:
hostname(config)# route if_name 0.0.0.0 0.0.0.0 gateway_ip [distance]
Tip You can enter 0 0 instead of 0.0.0.0 0.0.0.0 for the destination network address and mask, for example:
hostname(config)# route outside 0 0 192.168.1 1
The following example shows an FWSM configured with three equal cost default routes. Traffic received
by the FWSM for which there is no static or learned route is distributed among the gateways with the IP
addresses 192.168.2.1, 192.168.2.2, 192.168.2.3.
hostname(config)# route outside 0 0 192.168.2.1
hostname(config)# route outside 0 0 192.168.2.2
hostname(config)# route outside 0 0 192.168.2.3
Catalyst 6500 Series Switch and Cisco 7600 Series Router Firewall Services Module Configuration Guide using ASDM
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