AIS Router AI2524 User Manual
Page 176

AI2524 Router Card User’s Manual
Page 9-18
August 1997
2524UM
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:
z
Enable split horizon for ISO IGRP updates.
clns split-horizon
