Command References
Tables 22-5 and 22-6 list configuration and verification commands used in this chapter. As an easy review exercise, cover the left column in a table, read the right column, and try to recall the command without looking. Then repeat the exercise, covering the right column, and try to recall what the command does.
Table 22-5 Chapter 22 Configuration Command Reference
Command |
Description |
|---|---|
router ospf process-id |
Global command that enters OSPF configuration mode for the listed process |
network ip-address wildcard-mask area area-id |
Router subcommand that enables OSPF on interfaces matching the address/wildcard combination and sets the OSPF area |
ip ospf process-id area area-number |
Interface subcommand to enable OSPF on the interface and to assign the interface to a specific OSPF area |
ip ospf cost interface-cost |
Interface subcommand that sets the OSPF cost associated with the interface |
bandwidth bandwidth |
Interface subcommand that directly sets the interface bandwidth (Kbps) |
auto-cost reference-bandwidth number |
Router subcommand that tells OSPF the numerator in the Reference_bandwidth/Interface_bandwidth formula used to calculate the OSPF cost based on the interface bandwidth |
router-id id |
OSPF command that statically sets the router ID |
interface loopback number |
Global command to create a loopback interface and to navigate to interface configuration mode for that interface |
Table 22-6 Chapter 22 EXEC Command Reference
Command |
Description |
|---|---|
show ip ospf |
Lists information about the OSPF process running on the router, including the OSPF router ID, areas to which the router connects, and the number of interfaces in each area. |
show ip ospf interface brief |
Lists the interfaces on which the OSPF protocol is enabled (based on the network commands), including passive interfaces. |
show ip ospf interface [type number] |
Lists a long section of settings, status, and counters for OSPF operation on all interfaces, or on the listed interface, including the Hello and Dead Timers. |
show ip protocols |
Shows routing protocol parameters and current timer values. |
show ip ospf neighbor [type number] |
Lists brief output about neighbors, identified by neighbor router ID, including current state, with one line per neighbor; optionally, limits the output to neighbors on the listed interface. |
show ip ospf neighbor neighbor-ID |
Lists the same output as the show ip ospf neighbor detail command, but only for the listed neighbor (by neighbor RID). |
show ip ospf database |
Lists a summary of the LSAs in the database, with one line of output per LSA. It is organized by LSA type (first type 1, then type 2, and so on). |
show ip route |
Lists all IPv4 routes. |
show ip route ospf |
Lists routes in the routing table learned by OSPF. |
clear ip ospf process |
Resets the OSPF process, resetting all neighbor relationships and also causing the process to make a choice of OSPF RID. |
Answers to the “Do I Know This Already?” quiz:
1 B 2 A 3 A, E 4 B 5 B 6 A, D