Cisco 642-902 Online Practice Questions and Exam Preparation

Cisco 642-902 Online Questions & Answers

• Question 131:

  Refer to the exhibit. ROUTE.com is planning to implement a secure OSPF network to support traffic between clients on the 172.16.10.0/24 network and the file server on the 172.16.20./24 network. You have been asked to review the implementation and verification plans for this OSPF project. Which statement about the plan is true?

  

  A. It is complete as written.
  B. It should include a task that verifies that the interarea routes are using the proper MED.
  C. It should include a task that verifies that load sharing is active on R1 and R4.
  D. It should include a task that verifies that all redundant links will become active when the primary links are shut down.
  D. It should include a task that verifies that all redundant links will become active when the primary links are shut down.

  ---

  Reference: http://www.cisco.com/en/US/docs/routers/access/as5350/software/feature/guide/pull_rlm.htm l

• Question 132:

  Refer to the exhibit.

  

  Which statement is true?

  A. Router RTA is directly connected to interface 192.168.45.1.
  B. Neighbor 192.168.45.1 has changed its OSPF priority number.
  C. Router RTA and neighbor 192.168.45.2 are exchanging OSPF LSAs.
  D. Router RTA is the BDR.
  D. Router RTA is the BDR.

  ---

  There are only 3 routers in this segment. From the output we learn that RTB (10.0.0.2) is the DR and RTC (10.0.0.1) is not the DR or BDR so we can deduce RTA is the BDR.

• Question 133:

  Using the rules for IPv6 addressing, how can the address 2031:0000:240F:0000:0000:09C0:123A:121B be rewritten?

  A. 2031:0:240F::09C0:123A:121B
  B. 2031::240F::09C0:123A:121B
  C. 2031::240F:9C0::123A:121B
  D. 2031::240F:::09C0:123A:121B
  A. 2031:0:240F::09C0:123A:121B

  ---

  Leading zeros can be truncated. For example "0000 can be be just written as empty. In the above example :: indicates that it has multiple 0s in that location. Typically the IPv6 format can be written down in three ways 1) compressed, 2) uncompressed and 3) fully uncompressed as shown below. All of the following are the same:

  IPv6 Compressed (0000 is not displayed) 2002:4559:1FE2::4559:1FE2 IPv6 Uncompressed (0000 is displayed as 0) 2002:4559:1FE2:0:0:0:4559:1FE2 IPv6 Fully Uncompressed (0000 is fully displayed) 2002:4559:1FE2:0000:0000:0000:4559:1FE2

• Question 134:

  During a redistribution of routes from OSPF into EIGRP, an administrator notices that none of the OSPF routes are showing in EIGRP. What are two possible causes? (Choose two.)

  A. incorrect distribute lists have been configured
  B. missing ip classless command
  C. CEF not enabled
  D. no default metric configured for EIGRP
  A. incorrect distribute lists have been configured
  D. no default metric configured for EIGRP

  ---

  An incorrect distribute list can filter out updates therefore none of the OSPF routes are showing in EIGRP.

  The default metric when redistributing into EIGRP is infinite so we must specify a seed metric for EIGRP to work with.

• Question 135:

  Which two methods advertise internal networks to external ISPs via BGP? (Choose two.)

  A. using aggregate routes
  B. disabling synchronization C. forcing the next-hop address
  D. defining routes via the network statement
  A. using aggregate routes
  D. defining routes via the network statement

  ---

  In BGP, the network command tells the BGP process what locally learned networks to advertise. The networks can be connected routes, static routes, or routes learned by way of a dynamic routing protocol, such as RIP. These networks must also exist in the routing table of the local router or they will not be sent out in updates. The mask keyword can be used with the network command to specify individual subnets. Routes learned by the BGP process are propagated by default but are often filtered by a routing policy. Router(config-router)#network network-number [mask network-mask]

• Question 136:

  Refer to the exhibit.

  

  Which three statements accurately describe the result of applying the exhibited route map? (Choose three.)

  A. All routes that do no match clauses 10 and 20 of the route map are redistributed with their tags set to 8.
  B. The map prohibits the redistribution of all type 2 external OSPF routes.
  C. The map permits the redistribution of all type 1 external OSPF routes.
  D. The map prohibits the redistribution of all type 2 external OSPF routes with tag 6 set.
  A. All routes that do no match clauses 10 and 20 of the route map are redistributed with their tags set to 8.
  C. The map permits the redistribution of all type 1 external OSPF routes.
  D. The map prohibits the redistribution of all type 2 external OSPF routes with tag 6 set.

  ---

  The route-map command is used to configure policy routing, which is often a complicated task. A route map is defined using the syntax shown in the figure.

  Syntax:

  RouterA(Config)#route-map map-tag [permit | deny ] RouterA(Config-map-router)# The map-tag is the name, or ID, of the route map. This map-tag can be set to something easily recognizable name. The route-map

  command changes the mode on the router to the route-map configuration mode, from there conditions can be configured for the route map.

  In this example, the first route-map entry (10) will deny all type 2 routes with a tag of 6 (both must be true). The second route map (20) will set the metrics for all routes matching the pfx prefix list. Choice A is incorrect because the metrics

  shown do not need to match. These metrics will be assigned to the routes that match.

  The last route-map (30) will set all other routes that did not already match 10 or 20 with a tag of 8.

• Question 137:

  BGP contains two paths to a destination. Assuming both routes were originated locally and have an equal weight. What will be the next determining factor in choosing the best path?

  A. lowest MED
  B. highest local preference
  C. lowest neighbor IP address
  D. lowest origin code
  E. shortest AS-path
  B. highest local preference

  ---

  Memorizing the BGP decision process steps is very useful and you should remember them. The table below lists the complete path selection process:

  1.

  Weight (Bigger is better)

  2.

  Local preference (Bigger is better)

  3.

  Self originated (Locally injected is better than iBGP/eBGP learned)

  4.

  AS-Path (Smaller is better)

  5.

  Origin (Prefer ORIGIN code I over E, and E over ?)

  6.

  MED (Smaller is better)

  7.

  External (Prefer eBGP over iBGP)

  8.

  IGP cost (Smaller is better)

  9.

  EBGP Peering (Older is better)

  10.

  RID (Lower is better)

• Question 138:

  Based on the P1R3 show ip bgp output, which statement is true?

  

  A. The best path to reach the 192.168.11.0 prefix is via 10.200.200.11.
  B. The best path to reach the 192.168.11.0 prefix is via 10.200.200.12.
  C. The best path to reach the 192.168.11.0 prefix is via both 10.200.200.11 and 10.200.200.12; BGP will automatically load balance between the two.
  D. The 192.168.11.0 and 192.168.12.0 prefixes were learned via EBGP from the 10.200.200.11 and 10.200.200.12 EBGP neighbors.
  B. The best path to reach the 192.168.11.0 prefix is via 10.200.200.12.

  ---

  The best path to any given destination is noted by the ">" in the IP BGP table. In this case, the best path to 192.168.11.0 is via next hop 10.200.200.12 due to the fact that the weight is higher (101) than the path via the alternative next hop. Weight is a cisco proprietary method for path determination and the weight value is used above all other values.

• Question 139:

  According to RFC 2328, what is the stateful order in which an OSPF router transitions to a full adjacency with a neighbor router?

  A. Down, Init, 2-Way, Exstart, Exchange, Loading, and Full
  B. Down, Init, 2-Way, Exchange, Exstart, Loading, and Full
  C. Down, 2-Way, Init, Loading, Exstart, Exchange, and Full
  D. Down, 2-Way, Init, Exchange, Exstart, Loading, and Full
  E. Down, Init, 2-Way, Loading, Exstart, Exchange, and Full
  F. Down, 2-Way, Init, Exstart, Exchange, Loading, and Full
  A. Down, Init, 2-Way, Exstart, Exchange, Loading, and Full

  ---

  When OSPF adjacency is formed, a router goes through several state changes before it becomes fully adjacent with its neighbor. The states are Down - > Attempt (optional) -> Init -> 2-Way -> Exstart -> Exchange -> Loading -> Full. Short

  descriptions about these states are listed below:

  Down: no information (hellos) has been received from this neighbor.

  Attempt: only valid for manually configured neighbors in an NBMA environment. In Attempt state, the router sends unicast hello packets every poll interval to the neighbor, from which hellos have not been received within the dead interval.

  Init: specifies that the router has received a hello packet from its neighbor, but the receiving router's ID was not included in the hello packet 2-Way: indicates bi-directional communication has been established between two routers.

  Exstart: Once the DR and BDR are elected, the actual process of exchanging link state information can start between the routers and their DR and BDR.

  Exchange: OSPF routers exchange database descriptor (DBD) packets

  Loading: In this state, the actual exchange of link state information occurs

  Full: routers are fully adjacent with each other

  (Reference:

  http://www.cisco.com/en/US/tech/tk365/technologies_tech_note09186a0080093f0e.shtml)

• Question 140:

  Which of the below mentioned conditions form a neighbor relation in EIGRP? (Choose Three)

  A. Hello or ACK received
  B. AS number match
  C. Hello timer match
  D. Identical metric(k values)
  E. Dead Timer Match
  F. Network Time Match
  A. Hello or ACK received
  B. AS number match
  D. Identical metric(k values)

  ---

  EIGRP routers create a neighbor relationship by exchanging hello packets. Certain fields in the hello packets must match before an EIGRP neighbor relationship is established:

  EIGRP autonomous system (AS) number EIGRP K values