Cisco 642-902 Online Practice Questions and Exam Preparation

Cisco 642-902 Online Questions & Answers

• Question 91:

  To configure 6to4 tunneling on a dual-stack edge router. Which three of the following are valid components in 6to4 Tunneling configuration? (Choose Three)

  A. IPv4 Tunnel IP address
  B. Tunnel mode (6to4)
  C. Tunnel Keepalives
  D. IPv4 Tunnel Destination
  E. IPv4 Tunnel Source
  F. 6to4 IPv6 address (within 2002::/16)
  B. Tunnel mode (6to4)
  E. IPv4 Tunnel Source
  F. 6to4 IPv6 address (within 2002::/16)

  ---

  Reference: http://packetlife.net/blog/2010/mar/15/6to4-ipv6-tunneling/ (see 6to4 configuration, all three bullets)

• Question 92:

  Refer to the exhibit.

  

  A Boston company bought the assets of a New York company and is trying to route traffic between the two data networks using EIGRP over EoMPLS. As a network consultant, you were asked to verify the interoperability of the two networks. From the show ip route command output, what can you tell the customer about the traffic flow between the subnet in New York (172.16.8.0/24) and the subnets in Boston (172.16.16.0/24 and 10.10.16.0/24)?

  A. Traffic is flowing between the 172.16.8.0 subnet and subnets 172.16.16.0 and 10.10.16.0 and no configuration changes are needed.
  B. Auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0 subnet and subnets 172.16.16.0 and 10.10.16.0.
  C. Traffic will flow between the 172.16.8.0 subnet and 172.16.16.0 without any further configuration changes. However, auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0 subnet and the 10.10.16.0 subnet.
  D. Auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0 subnet and the 172.16.16.0 subnet. However, traffic will flow between the 172.16.8.0 subnet and 10.10.16.0 without any further configuration changes.
  B. Auto-summary must be disabled on N1 and B1 before traffic can flow between the 172.16.8.0 subnet and subnets 172.16.16.0 and 10.10.16.0.

  ---

  Basically auto route summarization happens at the classful network boundary...so that would make N1 and B1 the locations that summarization would occur for the 172.16.0.0/16 classful networks.

  So if you left auto-summarization enabled on those 2 routers, you would have an issue with discontiguous networks being advertised by both routers N1 and B1 with their classful mask (172.16.0.0/16 and 10.0.0.0/8), which will cause you

  issues.

  Turning off auto-summarization on N2 and B2 wouldn't make any difference, as their networks wouldn't be summarized due to the fact that they are not meeting a classful boundary on their perspective routers.

• Question 93:

  If no metric is specified for the routes being redistributed into IS-IS, what metric value is assigned to the routes?

  A. 20
  B. 10
  D. 1
  C

  ---

  The IS-IS metric must be between 1 and 63. There is no default-metric option in IS-IS--you should define a metric for each protocol. If no metric is specified for the routes being redistributed into IS-IS, a metric value of 0 is used by default.

• Question 94:

  A network administrator would like to configure an EIGRP router as a stub router that advertises directly connected and summary routes only. What command must the administrator issue to accomplish this?

  A. eigrp stub
  B. eigrp stub connected
  C. eigrp stub summary
  D. eigrp stub connected static
  E. eigrp stub receive-only
  A. eigrp stub

  ---

  Reference: http://www.cisco.com/en/US/docs/ios/12_0s/feature/guide/eigrpstb.html#wp1036215

• Question 95:

  The 192.168.0.0 network is not being propagated throughout the network. Observe the BGP configuration commands from the advertising router. What is the reason the 192.168.0.0 route is not being advertised? router bgp 65111 neighbor 172.16.1.1 remote-as 65111 neighbor 172.16.2.1 remote-as 65112 network 192.168.0.0 network 10.0.0.0 ! ip route 192.168.0.0 255.255.0.0 null0

  A. The network 192.168.0.0 statement is missing mask 255.255.0.0
  B. The network 192.168.0.0 statement is missing mask 0.0.255.255.
  C. The network 10.0.0.0 statement is missing mask 255.0.0.0.
  D. The network 10.0.0.0 statement is missing mask 0.255.255.255.
  E. The auto-summary configuration is missing.
  A. The network 192.168.0.0 statement is missing mask 255.255.0.0

  ---

  The "network" statement in other routing protocols (EIGRP, OSPF, RIP...) is used to enable routing protocol on the interfaces within that "network" statement. But in BGP, the function of a network statement is to tell the router to search the IP routing table for a particular network, and if that network is found, originate it into the BGP database. But notice that you must have an exact match in the IP routing table to appear the network in the BGP routing table (in this case we don't see the auto-summary command so we suppose it is disabled in this case). For example:

  + network 10.10.10.0/8 will appear in BGP if network 10.10.10.0/8 appears in the IP routing table. + network 10.10.10.0/24 will appear in BGP if network 10.10.10.0/24 appears in the IP routing table.

  Therefore, in this question the static route "ip route 192.168.0.0 255.255.0.0 null0 was used to put a route to 192.168.0.0/16 into the routing table (although it points to Null0 but this command really makes that route appears in the routing table). But the "network 192.168.0.0 statement tells the router to lookup network 192.168.0.0/24 (if the network statement under BGP-mode does not specify a subnet mask, the default subnet mask of that class will be used). The router only finds network 192.168.0.0/16 -> The network 192.168.0.0 is not being propagated throughout the network because of the mismatch of the subnet mask.

  Just for your information, in fact we have to suppose there is no entry of the network 192.168.0.0/24 exist in the routing table except the static route "ip route 192.168.0.0 255.255.0.0 null0. If such an entry exists (for example, a directly connected entry like "C 192.168.0.0/24 is directly connected") then the router still advertises it with the "network 192.168.0.0 (without mask 255.255.0.0) command.

• Question 96:

  What is a key benefit of using a GRE tunnel to provide connectivity between branch offices and headquarters?

  A. authentication, integrity checking, and confidentiality
  B. less overhead
  C. dynamic routing over the tunnel
  D. granular QoS support
  E. open standard
  F. scalability
  C. dynamic routing over the tunnel

  ---

  Generic routing encapsulation. Tunneling protocol developed by Cisco that can encapsulate a wide variety of protocol packet types inside IP tunnels, creating a virtual point-to-point link to Cisco routers at remote points over an IP internetwork.

• Question 97:

  When troubleshooting an EIGRP connectivity problem, you notice that two connected EIGRP routers are not becoming EIGRP neighbors. A ping between the two routers was successful. What is the next thing that should be checked?

  A. Verify that the EIGRP hello and hold timers match exactly.
  B. Verify that EIGRP broadcast packets are not being dropped between the two routers with the show ip EIGRP peer command.
  C. Verify that EIGRP broadcast packets are not being dropped between the two routers with the show ip EIGRP traffic command.
  D. Verify that EIGRP is enabled for the appropriate networks on the local and neighboring router.
  D. Verify that EIGRP is enabled for the appropriate networks on the local and neighboring router.

  ---

  The point of this question is about the condition of establish EIGRP neighbor. You can use these ways to troubleshoot the EIGRP connectivity problem.

  1.

  Whether EIGRP is enabled for the proper networks.

  2.

  Whether the K values of EIGRP neighbors is the same.

  3.

  Whether EIGRP autonomous number is the same.

  Incorrect answers:

  *. EIGRP use multicast, not broadcast.

  *. EIGRP use multicast, not broadcast.

  *. Hello and hold timers match is the condition of establish OSPF neighbor,not EIGRP.

• Question 98:

  Refer to the exhibit.

  

  Based upon the configuration, you need to understand why the policy routing match counts are not increasing. Which would be the first logical step to take?

  A. Confirm if there are other problematic route-map statements that precede divert.
  B. Check the access list for log hits.
  C. Check the routing table for 212.50.185.126.
  D. Remove any two of the set clauses. (Multiple set clause entries will cause PBR to use the routing table.)
  B. Check the access list for log hits.

  ---

  First we should check the access-list log, if the hit count does not increase then no packets are matched the access-list -> the policy based routing match counts will not increase.

• Question 99:

  Refer to the exhibit. On the basis of the output from the show ipv6 interface command, what two statements must be true? (Choose two.)

  

  A. Interface Ethernet 0/0 was configured with the ipv6 ospf 1 area 1 command.
  B. Interface Ethernet 0/0 has been configured with the ipv6 ospf authentication ipsec spi 500 md5 command.
  C. OSPF version 3 is enabled to support IPv6.
  D. The IP address of the designated router (DR) is FE80::A8BB:CCFF:FE00:6E00.
  E. This is the designated router (DR) on the Ethernet 0/0 link.
  B. Interface Ethernet 0/0 has been configured with the ipv6 ospf authentication ipsec spi 500 md5 command.
  C. OSPF version 3 is enabled to support IPv6.

  ---

  Reference: http://www.cisco.com/en/US/docs/ios-xml/ios/iproute_ospf/configuration/15- mt/ip6-route-ospfv3-auth-ipsec.pdf (see page 4, step 4)

• Question 100:

  Route.com is a small IT corporation that is attempting to implement the network shown in the exhibit. Currently the implementation is partially completed.

  OSPF has been configured on routes Chicago and New York. The S0/0 interface on Chicago and the S0/1 interface on New York are in area 0. The loopback0 on New York is in Area 1. However, they cannot ping from the serial interface of the satellite router to the loopback interface of the New York router. You have been asked to complete the implementation to allow this ping.

  ROUTE.com's corporate implementation guideline requires: The OSPF process ID for all routers must be 24. The routing protocol for all each interface must be enabled under the routing process. The routing protocol must be enabled for each interface using the most specific wild card mask possible. The serial link between Seattle and Chicago must be in OSPF area 8. OSPF area 8 must not receive any inter-area or external routers. Network information Seattle S0/0 192.168.34.5/30 link between Seattle and Chicago Secret Password: Cisco Chicago S0/0 192.168.40.9/30 link between Chicago and New York S0/0 192.168.34.6/30 link between Chicago and New York Secret Password: Cisco

  

  Here is the solution: On Seattle Router: Router ospf 24 network 192.168.34.5 0.0.0.0 area 8 area 8 stub On Chicago Router: Router ospf 24 area 8 stub no-summary network 192.168.34.6 0.0.0.0 area 8 You have to configure area 8 stub on seattle router and no-summary on Chicago router. This will allow the ping to go through.