router(config-router)#is-type level-1 Router A interface Ethernet 0 ip address 10.1.3.1 255.255.255.0 ip router isis （在接口上激活IS-IS，使這個接口的IP子網能夠被發布） interface serial 0 ip address 10.1.4.1 255.255.255.0 ip router isis router isis net 49.0001.0000.0000.000a.00 （設置NET，49為area id，0001.0000000a為system id） is-type level-2-only 路由器類型為Level 2
Router B interface Ethernet 0 ip address 10.1.5.2 255.255.255.0 ip router isis interface Ethernet 1 ip address 10.1.6.2 255.255.255.0 ip router isis interface serial 0 ip address 10.1.4.2 255.255.255.0 ip router isis router isis net 49.0001.0000.0000.000b.00 is-type level-2-only
Router C interface Ethernet 0 ip address 10.1.7.3 255.255.255.0 ip router isis interface Ethernet 1 ip address 10.1.6.3 255.255.255.0 ip router isis router isis net 49.0001.0000.0000.000c.00 is-type level-2-only
