CCNP Route FAQ: OSPF Overview and Neighbor Relationships
Q1. A router has been configured with the commands router ospf 9, network 172.16.1.0 0.0.0.255 area 8, and network 172.16.0.0 0.0.255.255 area 9, in that order. No other OSPF-related commands have been configured. The answers list the IP addresses that could be assigned to this router’s Fa0/0 interface. Which answers list an IP address/prefix length that would cause the router to put Fa0/0 into area 9? (Choose two.)
e. None of the other answers is correct.
Q2. Which of the following is true about an OSPF area border router (ABR)?
a. The ABR must have multiple interfaces connected to the backbone area.
b. An ABR is a router with two interfaces, each connected to a different nonbackbone area.
c. The only requirement to be considered an ABR is at least one interface connected to the backbone area.
d. An ABR must have at least one interface in the backbone area plus at least one other interface in a nonbackbone area.
Q3. Which of the following can either directly or indirectly identify all the interfaces for which both 1) OSPF has been enabled and 2) OSPF is not passive? (Choose two.)
a. show ip ospf database
b. show ip ospf interface brief
c. show ip protocols
d. show ip route ospf
e. show ip ospf neighbors
Q4. Router R1 directly connects to subnet 10.1.1.0/24 with its Fa0/0 interface. R1 can ping four other working OSPF routers in that subnet. R1 is neither the designated router (DR) nor backup DR (BDR). OSPF is working correctly on all five routers. Which of the following is true on R1? (Choose two.)
a. The show ip ospf neighbors command lists two neighbors off Fa0/0.
b. The show ip ospf neighbors command lists four neighbors off Fa0/0.
c. The show ip ospf neighbors command lists two neighbors off Fa0/0 in the FULL state.
d. The show ip ospf neighbors command lists two neighbors off Fa0/0 in the DISCO state.
Q5. Routers R1 and R2 are OSPF neighbors using their Fa0/0 interfaces, respectively, using default settings for all timers. An engineer adds the ip ospf hello-interval 6 command to R1’s Fa0/0 configuration. Which of the following is true regarding the results from this change? (Choose 2)
a. The show ip ospf neighbor command on R1 lists the revised Hello timer.
b. The show ip ospf interface brief command on R1 lists the revised Hello timer.
c. The R1-R2 neighborship fails due to Hello timer mismatch.
d. The show ip ospf interface command on R1 lists the revised Hello timer.
Q6. Routers R1 and R2, OSPF neighbors in area 0 over their Fa0/0 interfaces (respectively), currently both successfully use OSPF MD5 authentication. The OSPF configuration includes the area 0 authentication command under the router ospf 1 command. Which of the following commands must have been configured on R1’s Fa0/0 interface? (Choose two.)
a. ip ospf authentication null
b. ip ospf authentication message-digest
c. ip ospf authentication-key whatever-it-is
d. ip ospf message-digest-key 1 md5 whatever-it-is
e. ip ospf md5 1 key whatever-it-is
Q7. Which of the following settings do not prevent two potential OSPF neighbors from becoming neighbors?
a. The interface used to connect to that neighbor being passive in the OSPF process
b. Duplicate OSPF router IDs
c. Mismatched dead timers
d. IP addresses of 10.1.1.1/24 and 10.2.2.2/24
e. Mismatched OSPF process IDs
Q8. A company has a Frame Relay WAN with one central-site router and 100 branch office routers. A partial mesh of PVCs exists: one PVC between the central site and each of the 100 branch routers. All routers use point-to-point subinterfaces and one subnet per PVC. Which of the following is true about OSPF in this design?
a. The central site router has 100 fully adjacent neighborships with the 100 branches.
b. The central site router has neighborships with all branch routers, but fully
adjacent neighbors with only two branches.
c. The central site router has a neighborship with the Frame Relay switch.
d. None of the other answers is correct.