Cisco 642-902 Online Practice Questions and Exam Preparation

Cisco 642-902 Online Questions & Answers

• Question 111:

  Refer to the exhibit.

  

  Looking at the topology diagram and the partial router configurations shown, which statement is true?

  A. A routing loop will occur due to mutual route redistribution occurring on R1 and R2.
  B. Suboptimal routing will occur due to mutual route redistribution occurring on R1 and R2.
  C. Additional route filtering configurations using route maps and ACLs are required on the R1 and R2 routers to prevent routing loops.
  D. R2 will not be able to redistribute the EIGRP subnets into OSPF, because R2 is missing the default seed metric for OSPF.
  E. The 10.1.1.0/24 subnet will appear as 10.0.0.0/8 in the R5 routing table.
  E. The 10.1.1.0/24 subnet will appear as 10.0.0.0/8 in the R5 routing table.

  ---

  RIPv1 is a classful routing protocol so the subnet 10.1.1.0/24 will be summarized to 10.0.0.0/8 in the R5 routing table. If we use RIPv2 on R1, R5 and use the "no auto-summary" command on R1 then the 10.1.1.0 subnet will appear in the routing table of R5. Notice that even if the "auto-summary" command is configured under "router eigrp 1 of R1 but when redistributing into another routing protocol EIGRP still advertises the detailed network.

• Question 112:

  

  The company and the company network have both been growing rapidly. Multiple adds, moves and changes have been applied to the network. Your boss has asked you to troubleshoot a recent OSPF synchronization problem that has arisen. There have been synchronization problems at separate locations in the OSPF area 0. There have been reported link failures during the rapid growth of the company network. You are required to resolve the OSPF problem. OSPF must be able to converge when the network changes. Refer to the information above to answer the following question Examine the following excerpt from the "show ip ospf" command on D1:

  Area BACKBONE (0) Number of interfaces in the this area is 1 Area has no authentication SPF algorithm last executed 00:00:31.280 ago SPF algorithm executed 5 times Area ranges are Number of LSA 13. Checksum Sum 0x16F0FD Number of opaque link LSA 0. Checksum Sum Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0 Area 16 Number of interfaces in this area is 2 Area has message digest authentication SPF algorithm last executed 00:00:34.928 ago SPF algorithm executed 7 times Area ranges are Number of LSA 5. Checksum Sum 0x02FCD3 Number of opaque link LSA 0. Checksum Sum Number of DCbitless LSA 0 Number of indication LSA 0 Number of DoNotAge LSA 0 Flood list length 0

  Based on the information shown above, what is most likely causing the different missing routes throughout the network?

  A. Area 16 is configured with authentication.
  B. Area 16 has been configured to use the same interfaces as Area 0.
  C. Area 0 and Area 32 have been configured with mismatched LSA numbers.
  D. Area 16 has been configured as a total stub network
  E. Area 16 has been configured as a stub network
  F. Area 0 is discontiguous.
  G. None of the above
  F. Area 0 is discontiguous.

  ---

  From the topology, we see D1 has 2 interfaces belong to Area 0, that are interfaces Fa0/1 and Fa0/2 but the output says there is only one interface in Area 0 (Number of interfaces in the this area is 1). Therefore we can deduce that a link in area 0 was down and area 0 is dis contiguous.

• Question 113:

  

  On router R2 and R3: Config t Router ospf 1 Redistribute eigrp 100 metric 100 subnets distance eigrp 90 105 Router eigrp 100 Redistribute ospf 1 metric 100000 10 200 10 1500 Then from R1 you should be able to ping

  172.16.1.100 Since R2 router has the potential to be the shortest path to OSPF network from loopback 101. So configure the router R2 to have redistributable eigrp.

• Question 114:

  A network administrator is troubleshooting a redistribution of RIP routes into OSPF. Given the exhibited configuration commands, which statement is true?

  

  A. Redistributed routes will be tagged as external type 1 (E1) with a metric of 30.
  B. Redistributed routes will be tagged as external type 2 (E2) with a metric of 20.
  C. Redistributed routes will maintain their original RIP routing metric.
  D. Redistributed routes will have a default metric of 0 and will be treated as unreachable and not advertised.
  E. Redistributed routes will have a default metric of 0 but will not be treated as reachable and will be advertised.
  B. Redistributed routes will be tagged as external type 2 (E2) with a metric of 20.

  ---

  By default, all routes redistributed into OSPF will be tagged as external type 2 (E2) with a metric of 20, except for BGP routes (with a metric of 1).

  Note: The cost of a type 2 route is always the external cost, irrespective of the interior cost to reach that route. A type 1 cost is the addition of the external cost and the internal cost used to reach that route.

• Question 115:

  When verifying OSPF virtual link problems, which is an important item to check on the two transit OSPF routers?

  A. OSPF process ID
  B. OSPF router ID
  C. OSPF network type
  D. OSPF memory usage
  E. OSPF CPU utilization
  F. OSPF stub area configurations
  B. OSPF router ID

  ---

  The OSPF router IDs of the two transit OSPF routers are used to form the virtual link (with the area area-id virtual-link neighbor-router-id command) so it is an important item to check -> B is correct.

• Question 116:

  When learning a new route, if a LSA received is not found in the topological database, what will an internal OSPF router do?

  A. The sequence numbers are checked, and if the LSA is valid it is entered into the topology database.
  B. The LSA is placed in the topological database and an acknowledgement is sent to the transmitting router.
  C. The LSA is dropped and a message is sent to the transmitting router.
  D. The LSA is flooded immediately out of all the OSPF interfaces, except the interface from which the LSA was received.
  D. The LSA is flooded immediately out of all the OSPF interfaces, except the interface from which the LSA was received.

  ---

  Internal routers flood the area with new LSA's, and ABR's create and flood each area they are in with LSA's. The sequencing happens at the 2-way/ exstart stage, when exchanging the DBD.

• Question 117:

  Refer to the exhibit.

  

  It is desired to set up a BGP neighbor relationship between routers R1 and R4. BGP packets between them could travel through R2 or R3. What is the simplest configuration that will allow for failover?

  A. Configure BGP neighbor relationships between all interfaces on R1 and R4
  B. Install a direct connection between R1 and R4.
  C. Configure loopback interfaces on R1 and R4 to provide the update source address for BGP packets.
  D. Configure only one neighbor relationship between R1's 192.168.1.2 interface and R4's 172.16.10.2 interface.
  C. Configure loopback interfaces on R1 and R4 to provide the update source address for BGP packets.

  ---

  Assume R4 only uses this configuration:

  R4(config)#router bgp 65000

  R4(config-router)#neighbor 192.168.1.2 remote-as 65000 Then if R1 sends BGP packets to R4 via R3, the source IP address of the packets is 192.168.2.2. But R4 does not recognize this IP address because 192.168.2.2 is not configured in

  the "neighbor" command of R4. Therefore the IBGP session between R1 and R4 is not established -> these packets will be dropped.

  The simplest configuration to allow R1 and R4 communicate via both R2 and R3 is to use a loopback interface address rather than a physical interface address as the source IP address for all BGP packets. To do this, use the command:

  R4(config-router)#neighbor 1.1.1.1 update-source loopback0 (In which 1.1.1.1 is the loopback interface of R1). In practical, we should establish neighborship with the loopback interface rather than the physical interface because if the physical

  interface goes down, the neighborship would be lost while a loopback interface never goes down.

  Also, when configuring "1.1.1.1 as the neighbor, you must configure on R1 the "neighbor 4.4.4.4 update-source loopback0" command so that the source IP address of packets sent from R1 (loopback0 1.1.1.1) will be matched with the

  neighbor command configured on R4.

• Question 118:

  Refer to the exhibit.

  

  Which statement is true?

  A. RTA will redistribute the RIP routers into the NSSA as type 7 LSAs. RTB will translate the type 7 LSAs into type LSAs and flood them throughout the OSPF backbone.
  B. RTA will redistribute the RIP routers into the NSSA as type 7 LSAs. RTB will flood the type 7 LSAs throughout the backbone.
  C. RTA will redistribute the RIP routers into the NSSA as type 5 LSAs. RTB will flood the type 5 LSAs throughout the backbone.
  D. RTA will redistribute the RIP routers into the NSSA as type 5 LSAs. RTB will translate the type of 5 LSAs unto type 7 LSAs and flood them throughout the OSPF backbone.
  E. RTA will not redistribute the RIP routers into the NSSA.
  A. RTA will redistribute the RIP routers into the NSSA as type 7 LSAs. RTB will translate the type 7 LSAs into type LSAs and flood them throughout the OSPF backbone.

  ---

  Reference: https://www.google.com/url?

  sa=tandrct=jandq=andesrc=sandsource=webandcd=7andcad=rjaandved=0CFoQFjAGandurl=http%3A %2F%2Fdocs.dsl.net.pk%2FCisco%2FOSPF%2Fcis185-BSCI- lecture5-MultiArea-OSPFPart2.pptandei=8GWsUcX8EpG5hAeu34HAAgandusg=AFQjCNGj_IgwFjjBrjXr5hyCuTvY2ic Pagandsig2=wOzZ7YkgFK9aVKP8VB_b_Qandbvm=bv.47244034,d.ZG4 (See slide 9, 10 and

  11)

• Question 119:

  Which two among the following are used to indicate external type of route in routing table? (Choose two.)

  A. D EX
  B. IA
  C. O E2
  D. R E2
  E. i L2
  A. D EX
  C. O E2

  ---

  Reference: http://www.xpresslearn.com/cisco/routing/route-table-

• Question 120:

  Refer to the exhibit.

  

  Routers R1 and R2 have been configured to operate with OSPF. Routers R1 and R3 have been configured to operate with RIP. After configuring the redistribution between OSPF and RIP on R1, no OSPF routes are distributed into RIP. What should be done to correct this problem?

  A. The redistribution command should be reentered with the match route-type parameter included.
  B. The redistribution command should be reentered with the route-map map-tag parameter included.
  C. The redistribution command should be reentered with the metric metric-value parameter included.
  D. Routes will first need to be distributed into another protocol, and then into RIP.
  C. The redistribution command should be reentered with the metric metric-value parameter included.

  ---

  Notice that RIP metric is based on hop count only, and the maximum valid metric is 15. Anything above 15 is considered infinite. By default, when no metric is assigned when redistributing from EIGRP, OSPF, IS-IS, BGP into RIP, the default metric will be infinite. Therefore we must define a metric that is understandable to the receiving protocol. Usually, we should use a small value (like 1, 2, 3) so that after redistributing, that route can be advertised through many routers (because the limit is 15).