AIS AI2524 user manual Allow Point-to-Point Updates for Igrp, Define Unequal-Cost Load Balancing

AI2524 Router Card User’s Manual

Create the IGRP Routing Process

To create the IGRP routing process, perform these required tasks start- ing in global configuration mode:

1.Enable an IGRP routing process, which places you in router con- figuration mode.

router igrp process number

2.Associate networks with an IGRP routing process. network network-number

IGRP sends updates to the interfaces in the specified networks. If an interface's network is not specified, it will not be advertised in any IGRP update.

It is not necessary to have a registered autonomous system number to use IGRP. If you do not have a registered number, you can create your own. We recommend that if you do have a registered number, you use it to identify the IGRP process.

Allow Point-to-Point Updates for IGRP

Because IGRP is normally a broadcast protocol, in order for IGRP routing updates to reach point-to-point or nonbroadcast networks, you must configure the Cisco IOS software to permit this exchange of rout- ing information.

To permit information exchange, define a neighboring router by typ- ing this command in router configuration mode:

neighbor ip-address

To control the set of interfaces with which to exchange routing up- dates, you can disable the sending of routing updates on specified in terfaces by configuring th passive-interfacecommand.

Define Unequal-Cost Load Balancing

IGRP can simultaneously use an asymmetric set of paths for a given destination. This feature is known as unequal-cost load balancing. Un- equal-cost load balancing allows traffic to be distributed among up to four unequal-cost paths to provide greater overall output and reliabil- ity. Alternate path variance (that is, the difference in desirability be tween the primary and alternate paths) is used to determine the feasibility of a potential route. Only paths that are feasible can be used for load balancing and are included in the routing table. These condi-

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