Cisco Systems 78-11741-02 RIP and Igrp Redistribution Example, Eigrp Redistribution Examples

Configuring IP Routing Protocol-Independent Features

IP Routing Protocol-Independent Configuration Examples

RIP and IGRP Redistribution Example

Consider a WAN at a university that uses RIP as an interior routing protocol. Assume that the university wants to connect its WAN to a regional network, 172.16.0.0, which uses IGRP as the routing protocol. The goal in this case is to advertise the networks in the university network to the routers on the regional network. The commands for the interconnecting router are listed in the example that follows:

router igrp 1 network 172.16.0.0 redistribute rip

default-metric 10000 100 255 1 1500 distribute-list 10 out rip

In this example, the router global configuration command starts an IGRP routing process. The network router configuration command specifies that network 172.16.0.0 (the regional network) is to receive IGRP routing information. The redistribute router configuration command specifies that RIP-derived routing information be advertised in the routing updates. The default-metricrouter configuration command assigns an IGRP metric to all RIP-derived routes. The distribute-listrouter configuration command instructs the Cisco IOS software to use access list 10 (not defined in this example) to limit the number of entries in each outgoing update. The access list prevents unauthorized advertising of university routes to the regional network.

EIGRP Redistribution Examples

Each Enhanced IGRP (EIGRP) routing process provides routing information to only one autonomous system. The Cisco IOS software must run a separate EIGRP process and maintain a separate routing database for each autonomous system that it services. However, you can transfer routing information between these routing databases.

Suppose that the software has one EIGRP routing process for network 10.0.0.0 in autonomous system 71 and another EIGRP routing process for network 192.168.7.0 in autonomous system 1, as the following commands specify:

router eigrp 71 network 10.0.0.0

router eigrp 1 network 192.168.7.0

To transfer a route from 192.168.7.0 into autonomous system 71 (without passing any other information about autonomous system 1), use the command in the following example:

router eigrp 71

redistribute eigrp 1 route-map 1-to-71 route-map 1-to-71 permit

match ip address 3

set metric 10000 100 1 255 1500 access-list 3 permit 192.168.7.0

The following example is an alternative way to transfer a route to 192.168.7.0 into autonomous system 71. Unlike the previous configuration, this one does not allow you to arbitrarily set the metric.

router eigrp 71 redistribute eigrp 1 distribute-list 3 out eigrp 1

access-list 3 permit 192.168.7.0

Cisco IOS IP Configuration Guide

IPC-382