Configure IS-IS Layer Attribute
Configuration Condition
Before configuring the IS-IS layer attribute, first complete the following tasks:
- Configure the IP address of the interface to enable the neighboring nodes to be reachable at the network layer.
- Enable the IS-IS protocol.
Configure IS-IS Layer Attribute
The IS-IS layer attribute is divided into the global layer attribute and the interface layer attribute. The global layer attribute is the IS-IS intermediate system, which is further classified into the following three types:
- Level-1 intermediate system: Only the link status database of Level-1 is available and only the routing in the Level-1 area can be advertized and learnt.
- Level-2 intermediate system: Only the link status database of Level-2 is available and only the routing in the Level-2 area can be advertized and learnt.
- Level-1-2 intermediate system: Both the link status database of Level-1 and Level-2 are available and both the routing in the Level-1 and Level-2 area can be advertized and learnt. The Level-1-2 intermediate system is the interconnection device in the Level-1 and Level-2 area.
The layer attribute of the IS-IS interface is classified into the following three types:
- Level-1 attribute interface: Only the Level-1 packet of the IS-IS protocol can be transmitted and received and only the neighbor of Level-1 can be established.
- Level-2 attribute interface: Only the Level-2 packet of the IS-IS protocol can be transmitted and received and only the neighbor of Level-2 can be established.
- Level-1-2 attribute interface: Both the Level-1 packet and Level-2 packet of the IS-IS protocol can be transmitted and received and both the neighbors of Level-1 and Level-2 can be established.
The IS-IS interface layer attribute depends on the IS-IS global layer attribute. The Level-1 intermediate system only has the interface of Level-1 attribute, the Level-2 intermediate system only has the interface of Level-2 attribute, and the Level-1-2 intermediate system can has interfaces of all attributes.
Table 9-4 Configure the IS-IS global layer attribute
Step
|
Command
|
Description
|
Enter the global configuration mode
|
configure terminal
|
-
|
Enter the IS-IS configuration mode
|
router isis [area-tag]
|
-
|
Configure the IS-IS global layer attribute
|
is-type { level-1 | level-1-2 | level-2-only }
|
Optional
By default, the IS-IS global layer attribute is Level-1-2.
|
Table 9-5 Configure the IS-IS interface layer attribute
Step
|
Command
|
Description
|
Enter the global configuration mode
|
configure terminal
|
-
|
Enter the interface configuration mode
|
interface interface-name
|
-
|
Configure the interface layer attribute
|
isis circuit-type [ level-1 | level-1-2 | level-2 ]
|
Optional
By default, the interface layer attribute is consistent with the global layer attribute when the interface layer attribute is not specified.
|
![note](/storage/images/Document/Maipu/note-icon.jpg)
-
Only one IS-IS process with the Level-2 attribute is available in a VRF.