Using Route Maps To Redistribute Routing Information - Cisco WS-CBS3032-DEL Software Configuration Manual

Chapter 39 Configuring IP Unicast Routing
If a router has a directly connected interface to the specified default network, the dynamic routing
protocols running on that device generate a default route. In RIP, it advertises the pseudonetwork 0.0.0.0.
A router that is generating the default route for a network also might need a default route of its own. One
way a router can generate its own default router is to specify a static route to the network 0.0.0.0 through
the appropriate device.
Beginning in privileged EXEC mode, follow these steps to define a default static route to a network:
Command
Step 1 configure terminal
Step 2 ip default-network network number
Step 3
end
Step 4 show ip route
Step 5 copy running-config startup-config
Use the no ip default-network network number global configuration command to remove the route.
When default information passes through a dynamic routing protocol, no further configuration is
required. The system periodically scans its routing table to choose the best default network as its default
route. IGRP networks might have several candidate networks for the system default. Cisco routers use
administrative distance and metric information to set the default route or the gateway of last resort.
If dynamic default information is not being passed to the system, you can specify candidates for the
default route with the ip default-network global configuration command. If this network appears in the
routing table from any source, it is flagged as a possible choice for the default route. If the router has no
interface on the default network, but does have a path to it, the network is considered as a possible
candidate, and the gateway to the best default path becomes the gateway of last resort.

Using Route Maps to Redistribute Routing Information

The switch can run multiple routing protocols simultaneously, and it can redistribute information from
one routing protocol to another. Information redistribution from one routing protocol to another applies
to all supported IP-based routing protocols.
You can also conditionally control the redistribution of routes between routing domains by defining
enhanced packet filters or route maps between the two domains. The match and set route-map
configuration commands define the condition portion of a route map. The match command specifies that
a criterion must be matched. The set command specifies an action to be taken if the routing update meets
the conditions defined by the match command. Although redistribution is a protocol-independent
feature, some of the match and set route-map configuration commands are specific to a particular
protocol.
One or more match commands and one or more set commands follow a route-map command. If there
are no match commands, everything matches. If there are no set commands, only the match action
occurs. Therefore, you need at least one match or set command.
Note A route map with no set route-map configuration commands is sent to the CPU, which causes high CPU
utilization.
OL-13270-06
Purpose
Enter global configuration mode.
Specify a default network.
Return to privileged EXEC mode.
Display the selected default route in the gateway of last resort output.
(Optional) Save your entries in the configuration file.
Cisco Catalyst Blade Switch 3130 and 3032 for Dell Software Configuration Guide
Configuring Protocol-Independent Features
39-99