AI2524 Router Card User’s Manual

Warning: Adjusting the ISO IGRP metric can dramatically affect network performance, so ensure that all metric adjust- ments are made carefully. Because of the complexity of this task, it is not recommended unless it is done with guidance from an experienced system designer.

You can use different metrics for the ISO IGRP routing protocol on CLNS. In router configuration mode, configure the metric constants used in the ISO IGRP composite metric calculation of reliability and load:

metric weights qos k1 k2 k3 k4 k5

Two additional ISO IGRP metrics can be configured: the bandwidth and delay associated with an interface.

Warning: Using the bandwidth and delay commands to change the values of the ISO IGRP metrics also changes the val- ues of IP IGRP metrics.

Adjust ISO IGRP Timers

The basic timing parameters for ISO IGRP are adjustable. Because the ISO IGRP routing protocol executes a distributed, asynchronous rout- ing algorithm, it is important that these timers be the same for all rout- ers in the network.

In router configuration mode, adjust ISO IGRP timing parameters:

timers basic update-interval holddown- interval invalidinterval

Enable or Disable Split Horizon

Split horizon blocks information about routes from being advertised out the interface from which that information originated. This feature usually optimizes communication among multiple routers, particularly when links are broken.

In interface configuration mode, either enable or disable split horizon for ISO IGRP updates:

zEnable split horizon for ISO IGRP updates. clns split-horizon

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2524UM

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AIS AI2524 user manual Adjust ISO Igrp Timers, Enable or Disable Split Horizon, Metric weights qos k1 k2 k3 k4 k5