In the previous example, ALA-A, ALA-B, and ALA-C are configured as level 1 systems. Level 1 systems communicate with other level 1 systems in the same area. In this example, ALA-A is modified to set the level capability to level 1/2, as shown in Figure: Configuring a level 1/2 area. Now, the level 1 systems in the area with NET 47.0001 forward PDUs to ALA-A for destinations that are not in the local area.
Figure: Configuring a level 1/2 area
The following example displays the command usage to configure a level 1/2 system.
A:ALA-A>config>router# isis
A:ALA-A>config>router>isis# level-capability level-1/2