AIS Router AI2524 - Manual (Page 150)

AI2524 Router Card User’s Manual
Page 8-12 August 1997
2524UM
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-interface command.
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-