Cisco ASR 9000 Series

PurposeCommand or Action
(Optional) Configures the system type (area or backbone router).is-type { level-1 | level-1-2 | level-2-only }
Step 4
Example:
RP/0/RSP0/CPU0:router(config-isis)# is-type
level-2-only
•
By default, every IS-IS instance acts as a level-1-2 router.
•
The level-1 keyword configures the software to perform Level
1 (intra-area) routing only. Only Level 1 adjacencies are
established. The software learns about destinations inside its
area only. Any packets containing destinations outside the area
are sent to the nearest level-1-2 router in the area.
•
The level-2-only keyword configures the software to perform
Level 2 (backbone) routing only, and the router establishes only
Level 2 adjacencies, either with other Level 2-only routers or
with level-1-2 routers.
•
The level-1-2 keyword configures the software to perform both
Level 1 and Level 2 routing. Both Level 1 and Level 2
adjacencies are established. The router acts as a border router
between the Level 2 backbone and its Level 1 area.
commit
Step 5
(Optional) Displays summary information about the IS-IS instance.
show isis [ instance instance-id ] protocol
Example:
RP/0/RSP0/CPU0:router# show isis protocol
Step 6
Configuring Single Topology for IS-IS
After an IS-IS instance is enabled, it must be configured to compute routes for a specific network topology.
This task explains how to configure the operation of the IS-IS protocol on an interface for an IPv4 or IPv6
topology.
Cisco ASR 9000 Series Aggregation Services Router Routing Configuration Guide, Release 5.3.x
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Implementing IS-IS
Configuring Single Topology for IS-IS