Configuring OSPF Routing参考.ppt

Configuring OSPF Configuring OSPF Routing Configuring Basic OSPF Configuring OSPF on Internal Routers of a Single Area Configuring OSPF for Multiple Areas OSPF Router ID The router is known to OSPF by the OSPF router ID number. LSDBs use the OSPF router ID to differentiate one router from the next. By default, the router ID is the highest IP address on an active interface at the moment of OSPF process startup. A loopback interface can override the OSPF router ID. If a loopback interface exists, the router ID is the highest IP address on any active loopback interface. The OSPF router-id command can be used to override the OSPF router ID. Using a loopback interface or a router-id command is recommended for stability. Loopback Interfaces OSPF router-id Command OSPF Router ID Verification Verifying OSPF Operation Verifying OSPF Operation (Cont.) Example: The show ip route ospf Command Example: The show ip ospf interface Command Example: The show ip ospf neighbor Command Summary Configuration of OSPF is a two-step process: Enter OSPF configuration with the router ospf command. Use the network command to describe which interfaces will run OSPF in which area. OSPF selects a router ID at startup time: The router ID’s specified in the router-id command under the OSPF process. Otherwise, the highest IP address of a loopback interface, if there are any, is used. By default, the highest IP address of all active interfaces Use the show ip ospf command to verify the router ID. Use the show ip protocols, show ip route ospf, show ip ospf interface, show ip ospf, and show ip ospf neighbor commands to verify OSPF operation. Configuring OSPF OSPF Network Types OSPF Network Types The three types of networks defined by OSPF are: Point-to-point: A network that joins a single pair of routers. Broadcast: A multiaccess broadcast network, such as Ethernet. Nonbroadcast multiaccess (also called NBMA): A network that interconnects more than two routers but that has no broadcast capability. F