System information

Configuring IS-IS
10-11
where:
level-1 indicates that a Level 1 adjacency may be established if there is at least
one area address in common between this system and its neighbors.
level-1-2 indicates that a Level 1 and 2 adjacency is established if the neighbor is
also configured as level-1-2 and there is at least one area in common. If there is
no area in common, a Level 2 adjacency is established.
level-2-only indicates that a Level 2 adjacency is established only if the neighbor
is configured exclusively to be a Level 2 router.
Configuring IS-IS Link-State Cost Metrics
You can configure a cost for a specified interface. A cost is an arbitrary routing metric
value assigned for crossing or intersecting networks. This metric can be applied to
both Level 1 and/or Level 2 routing.
Use the isis metric command in Interface Configuration mode, to configure the
metric cost for the specified IS-IS interface:
MOT(config-if)#isis metric <cost> {level-1 | level-2}
where:
cost is the assigned routing metric value for the interface.
level-1 is for Level 1 IS-IS routing.
level-2 is for Level 2 IS-IS routing.
Setting the Advertised Hello Interval
IS-IS hello packets are broadcast to discover the identity of neighboring IS-IS systems
and to determine whether the neighbors are Level 1 or Level 2 intermediate systems.
The hello-interval multiplier is the amount of time that the IS-IS routing interface can
tolerate not receiving hello packets from its neighboring IS-IS interface before
declaring the neighbor as being down.