Cisco 642-902 Online Practice Questions and Exam Preparation

Cisco 642-902 Online Questions & Answers

• Question 231:

  Refer to the exhibit.

  

  Routers RTA and RTB are running BGP but the session is active. What command needs to be added to establish the BGP session?

  A. ip route 10.10.10.1 255.255.255.255 s0/0 ip route 10.10.10.1 255.255.255.255 s0/1
  B. no synchronization
  C. network 10.10.10.0
  D. neighbor 10.10.10.1 next-hop-self
  A. ip route 10.10.10.1 255.255.255.255 s0/0 ip route 10.10.10.1 255.255.255.255 s0/1

  ---

  When BGP is running between routers in different autonomous systems, it is called External BGP (EBGP). When BGP is running between routers in the same AS, it is called Internal BGP (IBGP). BGP allows the path that packets take to be manipulated by the AS, as described in this module. It is important to understand how BGP works to avoid creating problems for your AS as a result of running BGP. A static route can be used to form an adjacency between EBGP neighbors.

• Question 232:

  DRAG DROP

  Select and Place:

  

  

• Question 233:

  OSPF is configured over a Frame Relay network as shown in the exhibit. All PVCs are active. However, R1 and R3 fail to see all OSPF routes in their routing tables. The show ip ospf neighbor command executed on R2 shows the state of the neighbors. What should be done to fix the problem?

  

  A. The ip ospf network non-broadcast command should be configured on each Frame Relay interface.
  B. The ip ospf network broadcast command should be configured on each Frame Relay interface.
  C. The neighbor command should be configured under the OSPF routing process on all routers.
  D. The ip ospf priority value on the hub router should be set to 0.
  E. The ip ospf priority value on the spoke routers should be set to 0.
  E. The ip ospf priority value on the spoke routers should be set to 0.

  ---

  In an NBMA network topology, neighbors are not discovered automatically. OSPF tries to elect a DR and a BDR due to the multi-access nature of the network, but the election fails since neighbors are not discovered because NBMA environment doesn't forward broadcast and multicast packets. Neighbors must be configured manually to overcome these problems. Also, additional configuration is necessary in a hub and spoke topology to make sure that the hub routers, which have connectivity with every other spoke router, are elected as the DR and BDR. You must set the spoke interfaces to an OSPF priority of zero, this ensures that the spokes will not become the DR or BDR.

• Question 234:

  Which statement is true about the command ipv6 ospf 1 area 0?

  A. It must be issued in router global configuration mode to enable the OSPF process for IPv6.
  B. It must be issued in interface configuration mode to enable the OSPF process for IPv6.
  C. It must be issued before the network command to enable the OSPF process for IPv6.
  D. It must be issued after the network command to enable the OSPF process for IPv6.
  B. It must be issued in interface configuration mode to enable the OSPF process for IPv6.

  ---

  Reference:

  http://www.6deploy.eu/workshops/kenya_20080617/IPv6%20Routing_OSPFv3_MP- BGP.pdf (Slide 29)

• Question 235:

  Which command should be added to RTB under router bgp 100 to allow only the external OSPF routes to be redistributed to RTC?

  A. redistribute ospf 1
  B. redistribute ospf 1 match external 1
  C. redistribute ospf 1 match external 2
  D. redistribute ospf 1 match external 1 external 2
  D. redistribute ospf 1 match external 1 external 2

  ---

  Use the external keyword along with the redistribute command under router bgp to redistribute OSPF external routes into BGP. With the external keyword, you have three choices: 1. redistribute both external type-1 and type-2 (Default) 2.

  redistribute type-1 3. redistribute type-2 Enter the commands in the configuration mode as described here:

  RTB(config-router)# router bgp 100 RTB(config-router)# redistribute ospf 1 match external.

• Question 236:

  After implementing EIGRP on your network, you issue the show ip eigrp traffic command on router C. The following output is shown:

  RouterC#show ip eigrp traffic IF-EIGRP Traffic Statistics for process 1 Hellos sent/received: 481/444 Updates sent/received: 41/32 Queries sent/received: 5/1 Replies sent/received: 1/4 Acks sent/received: 21/25 Input queue high water mark 2, 0 drops SIA-Queries sent/received: 0/0 SIA-Replies sent/received: 0/0

  Approximately 25 minutes later, you issue the same command again. The following output is shown:

  RouterC#show ip eigrp traffic IP-EIGRP Traffic Statistics for process 1 Hellos sent/received: 1057/1020 Updates sent/received: 41/32 Queries sent/received: 5/1 Replies sent/received: 1/4 Acks sent/received: 21/25 Input queue high water mark 2, 0 drops SIA-Queries sent/received: 0/0 SIA-Replies sent/received: 0/0

  Approximately 25 minutes later, you issue the same command a third time. The following output is shown: RouterC#show ip eigrp traffic IP-EIGRP Traffic Statistics for process 1 Hellos sent/received: 1754/1717 Updates sent/received: 41/32 Queries sent/received: 5/1 Replies sent/received: 1/4 Acks sent/received: 21/25 Input queue high water mark 2, 0 drops SIA-Queries sent/received: 0/0 SIA-Replies sent/received: 0/0

  What can you conclude about this network?

  A. The network has been stable for at least the last 45 minutes.
  B. There is a flapping link or interface, and router C knows an alternate path to the network.
  C. There is a flapping link or interface, and router A does not know an alternate path to the network.
  D. EIGRP is not working correctly on router C.
  E. There is not enough information to make a determination.
  A. The network has been stable for at least the last 45 minutes.

  ---

  In three times using the command, the "Queries sent/received" and "Replies sent/received" are still the same -> the network is stable.

• Question 237:

  A network administrator is managing a hub-and-spoke network with EIGRP routing that has been enabled. The hub router is trying to query a remote router. However, delays are occurring that are caused by certain paths being stuck in active (SIA). How should the administrator configure EIGRP in order to limit the scope of the query range and prevent SIA from occurring?

  A. Configure the hub router with a scope limit of 1.
  B. Configure the remote router with a scope limit of 1.
  C. Configure the hub to indicate that the remote router is a stub router.
  D. Configure the hub and remote router as stub routers.
  E. Configure the remote router as a stub router.
  F. Disable the SIA feature of EIGRP on the remote router.
  E. Configure the remote router as a stub router.

  ---

  Configuring a router as a stub also helps the rest of the network. Queries are responded to much quicker and convergence happens much faster. Sometimes a query can cause delays that result in the path being SIA. If the stub configuration is applied, the router responds to queries as inaccessible, thus limiting the scope of the query range and preventing SIA from occurring.

• Question 238:

  You have just completed an OSPF implementation. While executing your verification plan, you determine that R1 is not able to establish full OSPF adjacency with R2. The show ip ospf neighbor command output on R1 shows that R2 is stuck in the INIT state.

  What could be the cause of this problem?

  A. DR and BDR election errors between R1 and R2.
  B. The R2 router has not received the OSPF hello packets from the R1 router.
  C. Mismatched interface maximum transmission unit (MTU) configuration between the R1 and R2.
  D. Mismatched OSPF hello interval configuration between the R1 and R2.
  E. Corrupted LSAs exchanges between the R1 and R2.
  B. The R2 router has not received the OSPF hello packets from the R1 router.

  ---

  When a router receives an OSPF Hello from a neighbor, it sends the Hello packet by including that neighbor's router ID in the Hello packet. If the neighbor does not receive this packet (means that it doesn't see itself in this packet), it will be stuck in INIT state. INIT state can be understood as a one- way Hello. An example of a router stuck in INIT state is shown below:

  

• Question 239:

  Refer to the exhibit.

  

  Based on the command output, what is one reason why no routes from the OSPF neighbor 192.168.0.5 are installed in the IP routing table?

  A. R3 will only install routes from the neighbor with the lowest priority (Pri). If routes have the same priority, routes from the neighbor with the lowest IP address are used.
  B. R3 did not receive any LSAs from 192.168.0.5.
  C. Routes from backup designated routers are never installed in the IP routing table.
  D. 192.168.0.5 is a redundant link to 192.168.0.4, and load balancing is not enabled.
  B. R3 did not receive any LSAs from 192.168.0.5.

  ---

  R3 may not receive any LSAs from neighbor 192.168.0.5 because a distribute-list blocks it. But notice that the LSAs are not filtered out in the LSDB since all routers in an OSPF area must be the same (synchronized).

• Question 240:

  Company plans on migrating their network from IPv4 to IPv6 in the near future. Which three techniques can be used to transition from IPv4 to IPv6? (Select three)

  A. Dual stack
  B. NAT
  C. Flow label
  D. Mobile IP
  E. 6to4 tunneling
  F. Anycast
  G. MBGP
  A. Dual stack
  B. NAT
  E. 6to4 tunneling

  ---

  Reference: http://www.inethk.asia/docs/christian-ipv6-isp-perspective-ISOC.pdf (slide 9)