Cisco Systems 3560 Manual De Usuario

Beginning in privileged EXEC mode, follow these steps to define a static route to a network as the static 
default route:

Use the no ip default-network network number global configuration command to remove the route.

When default information is passed through a dynamic routing protocol, no further configuration is 
required. The system periodically scans its routing table to choose the optimal default network as its 
default route. In IGRP networks, there might be 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, candidates for the default route are 
specified 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.

The switch can run multiple routing protocols simultaneously, and it can redistribute information from 
one routing protocol to another. Redistributing information 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, nothing is done, other than 
the match. Therefore, you need at least one match or set command.

A route map with no set route-map configuration commands is sent to the CPU, which causes high CPU 
utilization.

Enter global configuration mode.

ip default-network network number 

Specify a default network.

end 

Return to privileged EXEC mode.

Display the selected default route in the gateway of last resort 
display.

(Optional) Save your entries in the configuration file.