4a0-c01 Actual Exam

By Author: Peter Baumann
Total Articles: 19
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Question: 1

Which of the following conditions will prevent an OSPF adjacency from reaching the full state? Choose three answers.

A. MTU mismatch
B. Incorrect subnet mask
C. System interface not included in OSPF
D. Area ID not the same
E. Different metric set on each end of the link
F. Router ID not defined

Answer: A, B, D

Question: 2

Click the exhibit button.

The following command sequence is executed on router R2:
A: R2# configure router ospf router-id 10.10.10.99
A: R2# configure router router-id 10.10.10.66
On router R1, what router ID appears for router R2 directly after these commands are executed?

A. 10.10.10.99
B. 10.10.10.66
C. 10.10.10.2
D. 10.10.10.1

Answer: C

Question: 3

In an OSPF Hello packet, which of the following fields must match for all neighbor routers on the segment? Choose three answers.

A. Area ID W B.
B. Hello and Dead intervals PC.
C. Stub flag
D. Checksum values
E. The list of neighbors

Answer: ...
... A, B, C

Question: 4

Click the exhibit button.


The OSPF adjacency between routers R3 and R1 is down. What is the problem?

A. Area 1 of router R1 should not be configured as a stub.
B. Router R3 has the incorrect authentication key type.
C. Router R1 has the incorrect authentication key type.
D. There is not enough information to tell.

Answer: C

Question: 5

Click the exhibit button.

Given the topology and the show commands, and assuming that router R2 advertises all of its loopbacks into OSPF, what is the correct router R1 configuration?

A. Option A
B. Option B
C. Option C
D. Option D

Answer: A

Question: 6

In which of the following types of areas does an OSPF router not set the E bit in its Type 1 LSA?

A. Not so stubby area
B. Stub area
C. Backbone area
D. Normal area

Answer: B

Question: 7

Click the exhibit button.

In the topology shown, router R1 is an ASBR configured to export external routes to OSPF. Which of the following statements regarding the OSPF LSAs in the network is true?

A. Router R1 generates a type 5 LSA that is flooded through all OSPF areas.
B. Router R1 generates a type 7 LSA that is flooded through all OSPF areas.
C. Router R1 generates a type 5 LSA that is flooded through area 1. Router R2 generates a type 7 LSA that is flooded through areas 0 and 2.
D. Router R1 generates a type 7 LSA that is flooded through area 1. Router R3 generates a type 5 LSA that is flooded through areas 0 and 2.

Answer: D

Question: 8

What is the protocol number for OSPF in the IP header?

A. OSPF uses TCP, so the protocol number is 6.
B. OSPF uses UDP, so the protocol number is 17.
C. OSPF does not use IP.
D. OSPF has its own protocol number of 89.

Answer: D

Question: 9

Click the exhibit button.

Which of the following would correctly configure routers R2, R3, and R4?

A. Option A
B. Option B
C. Option C
D. Option D

Answer: C

Question: 10

When are virtual links used in OSPF?

A. When two areas need to communicate and there is no area 0.
B. When an area needs to traverse another area to reach area 0.
C. When two areas are connected to area 0, but there is no direct path between them.
D. When an area needs to connect directly to another area without using area 0.

Answer: B

Question: 11

Which of the following statements regarding area border routers in an OSPF network is true?

A. The term backbone router has the same definition as the term area border router.
B. An OSPF network needs at least one area border router to function.
C. Area border routers connect the backbone area to other areas in an OSPF network.
D. By definition, an area border router must perform route summarization between areas.

Answer: C

Question: 12

Which of the following correctly lists the 5 OSPF packet types?

A. Hello, link state update, link state packet, link State acknowledgement, database description.
B. Link state update, link state refresh, link state acknowledgement, database description, notification.
C. Hello, link state refresh, link state update, link state acknowledgement, link state authentication.
D. Hello, link state update, link state request, link state acknowledgement, database description.

Answer: D
Question: 13

When a router receives an IP packet, but does not find a match in the routing table for the destination IP address, what actions are performed by the router?

A. The packet is flooded out all router interfaces.
B. The packet is dropped and an ICMP unreachable message is sent back to the source.
C. The packet is silently discarded.
D. The packet is flooded out all interfaces and an ICMP unreachable message is sent.

Answer: B

Question: 14

Which of the following statements regarding distance vectors protocols are true?
(Choose two answers).

A. RIPv1, RIPv2, and BGP are distance vector protocols.
B. OSPF and IS-IS are distance vector protocols.
C. Routing tables are exchanged between neighbors; however, no routing table is transmitted beyond the immediate neighbor.
D. Distance vector protocols use the Dijkstra SPF algorithm.
E. Routers that participate in distance vector routing protocols maintain full knowledge of distant routers and how they interconnect

Answer: A, C

Question: 15

Click the exhibit button.

Routers R1 „ R2, and R3 are running a classful routing protocol between them. Assuming that router R1 advertises all directly connected networks, how will these networks be represented in router R3's routing table?

A. Router R3's routing table can only contain one of the routes, which will result in route flapping.
B. Router R3's routing table will have one entry for 10.1.1.0/24 and one entry for 10.1.2.0/24.
C. The networks will be represented with one entry of 10.0.0.0/8 in router R3's routing table.
D. The networks will be represented with one entry of 10.0.0.0/24 in router R3's route table.

Answer: C

Question: 16

In an IP datagram, which of the following fields identifies the receiving application?

A. The protocol field of the transport layer header.
B. The port field of the transport layer header.
C. The protocol field of the network layer header.
D. The port field of the network layer address.

Answer: B

Question: 17

Static routing will be used in a network between a corporate head office, with many connected networks, and a branch office, with one connection to the head office. Which of the following best describes the likely configuration?

A. The corporate head office router will have a default route and the branch site will have a more specific static route.
B. The corporate head office router and the branch office router will both have specific static routes.
C. The corporate head office router and the branch router will both have default routes.
D. The corporate head office router will have a more specific static route and the branch office router will have a default route.

Answer: D

Question: 18

Click the exhibit button.

What is the command to configure a static route on the Alcatel-Lucent 7750 SR router R1 to reach the network behind router R2?

A. configure router static-route 139.120.121.0/24 next-hop 138.120.199.2
B. configure router static-route 139.120.121.0/24 next-hop 138.120.199.1
C. configure router static-route 138.120.199.2/24 next-hop 138.120.199.1
D. configure router static-route 139.120.121.0/24 next-hop 139.120.121.2

Answer: A

Question: 19

There is an IP host with IP address 10.2.3.1. A static route is created, using the "configure router static-route 10.2.3.0/24 next-hop 10.1.2.1" command. What is the correct traceroute command to test this static route on an Alcatel-Lucent 7750 SR?

A. traceroute 10.2.3.1
B. traceroute 10.2.3.1 next-hop 10.1.2.1
C. traceroute next-hop 10.1.2.1
D. traceroute does not work on the Alcatel-Lucent 7750 SR.
E. traceroute 10.1.2.1

Answer: A

Question: 20

Click the exhibit button.

A static route is created on router R1 "using the "static-route 0.0.0.0/0 next-hop 10.3.3.2" command. What command can be used to test the static route on an Alcatel-Lucent 7750 SR?

A. ping static 10.5.5.5
B. ping static 0.0.0.0/0
C. ping 10.5.5.5
D. ping 0.0.0.0

Answer: C

Question: 21

What is the default preference value for a static route in the Alcatel-Lucent 7750 SR?

A. 0
B. 5
C. 10
D. 15

Answer: B

Question: 22

Which of the following statements apply to link state protocol behavior? Choose three answers.

A. Routers broadcast the entire route table to all neighbors.
B. Information about directly connected links is sent to all neighbors.
C. An adjacency database is maintained by each router.
D. The sequence number for an update is incremented as it is flooded from router to router.
E. The topological database is the same for all routers in a single area.

Answer: B, C, E

Question: 23

Click the exhibit button.

What triggers convergence of the routing protocol when the link between switch 1 and switch 2 goes down?

A. Convergence is triggered when the adjacency between routers R1 and R2 drops as a result of Hello timeouts. At this point, both routers R1 and R2 re-compute their link state database and send updates to their adjacent routers. Once the process is complete for all routers, the networks have converged.
B. Convergence is triggered when the physical interfaces between routers R1 and R2 go down. At this point, both routers R1 and R2 re-compute their link state database and send updates to their adjacent routers. Once the process is complete for all routers, the networks have converged.
C. Convergence will not be triggered because switches cannot run routing protocols between them.
D. Convergence is triggered when the switches notify the routers about the link state information. At this point, both routers R1 and R2 re-compute their link state database and send updates to their adjacent routers. Once the process is complete for all routers, the networks have converged
E. Convergence is triggered when an LSA is sent from router R1 to router R2 to indicate that the link is down. At this point, both routers R1 and R2 re-compute their link state database and send updates to their adjacent routers. Once the process is complete for all routers, the networks have converged.

Answer: A

Question: 24

What are the default Hello and Dead timer intervals for OSPF on the Alcatel-Lucent 7750 SR?

A. 5 and 15 seconds
B. 10 and 30 seconds
C. 5 and 20 seconds
D. 10 and 40 seconds

Answer: D

Question: 25

What causes an adjacency to change from down to two ways?

A. When a link state update is received in response to a link state request.
B. When a router receives a Hello packet that contains its own router ID in the neighbor list from a neighbor.
C. When a router receives a database description packet from a neighbor.
D. When a link state acknowledgement is received in response to a link state update.

Answer: B

Question: 26

Click the exhibit button.

In the topology shown, router R1 is an ASBR configured to export external routes to OSPF. Assuming that there are no stub networks, which of the following statements regarding type 4 LSA generation is true?

A. Router R1 generates a type 4 LSA that is flooded to areas 0, 1, and 2.
B. Router R3 generates a type 4 LSA that is flooded to areas 0, 1, and 2.
C. Router R3 generates a type 4 LSA that is flooded to areas 0 and 2.
D. Router R3 generates a type 4 LSA that is flooded to area 0, and router R6 generates a type 4 LSA that is flooded to area 2.

Answer: D

Question: 27

Which of the following commands can be used to display the number of SPF computations that have been performed on a router?

A. show router ospf area
B. show router ospf neighbor
C. show router ospf interface
D. show router ospf status

Answer: A

Question: 28

Which of the following statements describe the major features of OSPF? Choose two answers.

A. Fast reroute capability
B. Control traffic prioritization
C. Route redistribution
D. Traffic engineering extensions
E. Cut through forwarding

Answer: C, D

Question: 29

Click the exhibit button.

What can you deduce from the show command on router R6?

A. The router R6 interface is in a multi-access segment. It is neither the DR nor the BDR for the segment. The DR for this segment would be the router with router ID 10.10.10.5.
B. The router R6 interface is in a multi-access segment. It is neither the DR nor the BDR for the segment; however, this command does not indicate whether 10.10.10.3 or 10.10.10.5 is the DR or BDR.
C. The router R6 interface is in a multi-access segment. It is the BDR, which is why it is not adjacent to the other routers.
D. The router R6 interface is in a multi-access segment. It is neither the DR nor the BDR for the segment. The DR for this segment would be the router with router ID 10.10.10.3.

Answer: B

Question: 30

Click the exhibit button.

In the topology shown, router R1 is an ASBR configured to export external routes to OSPF. How many type 4 LSAs will be present in the network?

A. One.
B. One for each of the routers in area 0
C. One for each of the external routes exported by router R1.
D. Type 4 LSAs are not generated in this network topology.

Answer: D