CCNA3 v6.0 Chapter 8 Exam Answers

1. What is used to create the OSPF neighbor table?

adjacency database*

link-state database

forwarding database

routing table


2. Which OSPF component is identical in all routers in an OSPF area after convergence?

adjacency database

link-state database*

routing table

SPF tree

3. Which OPSF packet contains the different types of link-state advertisements?






4. What happens immediately after two OSPF routers have exchanged hello packets and have formed a neighbor adjacency?

They exchange DBD packets in order to advertise parameters such as hello and dead intervals.

They negotiate the election process if they are on a multiaccess network.

They request more information about their databases.

They exchange abbreviated lists of their LSDBs.*

5. What will an OSPF router prefer to use first as a router ID?

any IP address that is configured using the router-id command*

a loopback interface that is configured with the highest IP address on the router

the highest active interface IP that is configured on the router

the highest active interface that participates in the routing process because of a specifically configured network statement

6. What are the two purposes of an OSPF router ID? (Choose two.)

to facilitate the establishment of network convergence

to uniquely identify the router within the OSPF domain*

to facilitate the transition of the OSPF neighbor state to Full

to facilitate router participation in the election of the designated router*

to enable the SPF algorithm to determine the lowest cost path to remote networks

7. By default, what is the OSPF cost for any link with a bandwidth of 100 Mb/s or greater?





8. Which command should be used to check the OSPF process ID, the router ID, networks the router is advertising, the neighbors the router is receiving updates from, and the default administrative distance?

show ip protocols*

show ip ospf neighbor

show ip ospf

show ip ospf interface

9. What are two reasons that will prevent two routers from forming an OSPFv2 adjacency? (Choose two.)

a mismatched Cisco IOS version that is used

mismatched OSPF Hello or Dead timers*

mismatched subnet masks on the link interfaces*

use of private IP addresses on the link interfaces

one router connecting to a FastEthernet port on the switch and the other connecting to a GigabitEthernet port

10. Which three addresses could be used as the destination address for OSPFv3 messages? (Choose three.)







11. A network administrator enters the command ipv6 router ospf 64 in global configuration mode. What is the result of this command?

The router will be assigned an autonomous system number of 64.

The router will be assigned a router ID of 64.

The reference bandwidth will be set to 64 Mb/s.

The OSPFv3 process will be assigned an ID of 64.*

12. When a network engineer is configuring OSPFv3 on a router, which command would the engineer issue immediately before configuring the router ID?

ipv6 ospf 10 area 0

ipv6 router ospf 10*

interface serial 0/0/1

clear ipv6 ospf process

13. Single area OSPFv3 has been enabled on a router via the ipv6 router ospf 20 command. Which command will enable this OSPFv3 process on an interface of that router?

ipv6 ospf 0 area 0

ipv6 ospf 20 area 20

ipv6 ospf 0 area 20

ipv6 ospf 20 area 0*

14. What does a Cisco router use automatically to create link-local addresses on serial interfaces when OSPFv3 is implemented?

the highest MAC address available on the router, the FE80::/10 prefix, and the EUI-48 process

the FE80::/10 prefix and the EUI-48 process

the MAC address of the serial interface, the FE80::/10 prefix, and the EUI-64 process

an Ethernet interface MAC address available on the router, the FE80::/10 prefix, and the EUI-64 process*

15. Which command will verify that a router that is running OSPFv3 has formed an adjacency with other routers in its OSPF area?

show running-configuration

show ipv6 ospf neighbor*

show ipv6 route ospf

show ipv6 interface brief

16. Which command will provide information specific to OSPFv3 routes in the routing table?

show ip route ospf

show ip route

show ipv6 route

show ipv6 route ospf*

17. Match the OSPF state with the order in which it occurs. (Not all options are used.)

Place the options in the following order:
second state  -> Init state
– not scored –
seventh state  -> Full state
fifth state  ->  Exchange state
first state  ->  Down state
fourth state  ->  Exstart state
– not scored –
third state  ->  Two-way state
sixth state  ->  Loading state

18. Match each OSPF packet type to how it is used by a router. (Not all options are used.)

establish and maintain adjacencies = hello packet

advertise new information = link-state update packet

compare local topology to that sent by another router = database description packet

query another router for additional information = link-state request packet

19. By order of precedence, match the selection of router ID for an OSPF-enable router to the possible router ID options. (Not all option are used.)

loopback interface address = Third precedence

Serial interface IP address = Fourth precedence

Configured router ID = First precedence

Loopback interface IP address = Second precedence

20. Match the information to the command that is used to obtain the information. (Not all options are used.)

show ip ospf neighbor = Neighbor ID of

show ip ospf = Routing Process “ospf 10” with ID

show ip protocols = Routing Protocol is “ospf 10”

show interface serial 0/0/0 = BW 1544 Kbit/sec

21. Fill in the blank.

OSPF uses “cost” as a metric.


22. Fill in the blank.

The election of a DR and a BDR takes place on “multiaccess” networks, such as Ethernet networks.

23. Open the PT Activity. Perform the tasks in the activity instructions and then complete the task.

What message is displayed on





Leave a Reply

This site uses Akismet to reduce spam. Learn how your comment data is processed.