isis circuit-type

isis circuit-type

Configures the type of IS-IS adjacency for an interface.

Syntax: isis circuit-type [level-1 | level-2 | level-2-only]

level-1

Establish a Level 1 adjacency if there is at least one area address in common between this system and its neighboring systems. If Level 1 is set, this interface cannot support Level 2 adjacencies.

level-l-2

Establish a Level 1 and Level 2 adjacency if a neighboring system is also configured as a Level -1-2 and there is at least one area address in common. If there is no area address in common, a Level 2 adjacency is established.

level-2-only

Establish a Level 2 adjacency if the neighboring system is configured as a Level 2-only router.

Level-1 routers route traffic within a single area. Level-2 routes route traffic between areas. Level 1-2 routers route both types of traffic.

NOTE It is not necessary to configure the circuit type on point-to-point interfaces.

Use the isis circuit-type level-1 command to configure the interface to support only intra-area traffic.

Use the isis-circuit-type level-1-2 command to configure the interface to support both intra-area traffic and inter-area traffic.

Use the isis circuit-type level-2-only command to configure the interface to support only Level-2 adjacencies. This option is used on routers that are between areas to prevent transmission of unnecessary Level 1 hellos.

Factory Default: Level 1-2 adjacency.

Command Mode: Interface configuration.

Example: In the following example:

The router isis command enables IS-IS on the router, specifies an IS-IS instance, and changes the command mode to Router configuration.

The net command configures a NET for the routing process.

The interface pos n/n/n identifies a specific POS interface and changes the command mode to Interface configuration.

The ip router isis command enables the IS-IS process specified by the global router isis command on the interface.

The isis circuit-type level-1 command configures the interface to support a Level-1 adjacency

The show running-config interface command displays the setting:

router(config)#router isis 1

router(config-router)#net 49.0001.0000.0000.1111.00

router(config-router)#interface pos 1/5/1

router(config-if)#ip router isis 1

router(config-if)#isis circuit-type level-1

router(config-if)#end

router#show running-config int

.

.

.

!

interface pos 1/5/1

sonet path-trace NPI1 1/5/1

ip address 10.100.53.2 255.255.255.0

crc 16

ip router isis npi

isis circuit-type level-1

.

.

.

Related Commands: ip router isis
isis priority
isis password
isis csnp-interval
isis hello-interval
isis metric
isis network-type
net
router isis

level-1	Establish a Level 1 adjacency if there is at least one area address in common between this system and its neighboring systems. If Level 1 is set, this interface cannot support Level 2 adjacencies.
level-l-2	Establish a Level 1 and Level 2 adjacency if a neighboring system is also configured as a Level -1-2 and there is at least one area address in common. If there is no area address in common, a Level 2 adjacency is established.
level-2-only	Establish a Level 2 adjacency if the neighboring system is configured as a Level 2-only router.

router(config)#router isis 1 router(config-router)#net 49.0001.0000.0000.1111.00 router(config-router)#interface pos 1/5/1 router(config-if)#ip router isis 1 router(config-if)#isis circuit-type level-1 router(config-if)#end router#show running-config int . . . ! interface pos 1/5/1 sonet path-trace NPI1 1/5/1 ip address 10.100.53.2 255.255.255.0 crc 16 ip router isis npi isis circuit-type level-1 . . .

   Source File Name: ISIS.fm
    HTML File Name: ISIS9.html
    Last Updated: 05/10/04 at 16:35:45

isis circuit-type

Please email suggestions and comments to: doc@avici.com