146• Configure an IP address for each interface, and make sure all neighboring nodes are reachable toeach other at the network layer.Enabling IS-ISFollow these steps to enable IS-IS:To do… Use the command… RemarksEnter system view system-view —Enable the IS-IS routing processand enter its viewisis [ process-id ] [ vpn-instancevpn-instance-name ]RequiredNot enabled by defaultAssign a network entity title (NET) network-entity net RequiredNot assigned by defaultReturn to system view quit —Enter interface view interface interface-typeinterface-number —Enable an IS-IS process on theinterface isis enable [ process-id ] RequiredDisabled by defaultConfiguring the IS level and circuit levelIf only one area is available, H3C recommends you to perform the following operations:• Configure the IS level of all routers as Level-1 or Level-2 rather than different levels because therouters do not need to maintain two identical LSDBs.• Configure the IS level as Level-2 on all routers in an IP network for scalability.For an interface of a Level-1 (or Level-2) router, the circuit level can only be Level-1 (or Level-2). For aninterface of a Level-1-2 router, the default circuit level is Level-1-2; if the router only needs to form Level-1 (orLevel-2) neighbor relationships, then configure the circuit level for its interfaces as Level-1 (or Level-2) tolimit neighbor relationship establishment.Follow these steps to configure the IS level and circuit level:To do… Use the command… RemarksEnter system view system-view —Enter IS-IS view isis [ process-id ] [ vpn-instancevpn-instance-name ] —Specify the IS level is-level { level-1 | level-1-2 |level-2 }OptionalThe default is Level-1-2.Return to system view quit —Enter interface view interface interface-typeinterface-number —Specify the circuit level isis circuit-level [ level-1 | level-1-2| level-2 ]OptionalBy default, an interface can establishthe Level-1 or Level-2 adjacency.
