Cisco 351-001 Online Practice Questions and Exam Preparation

Cisco 351-001 Online Questions & Answers

• Question 281:

  Which problem can result when private AS numbers are included in advertisements that are sent to the global Internet BGP table?

  A. The prefixes sent with private AS numbers are always discarded on the Internet.
  B. The prefixes sent with private AS numbers are always tagged as invalid on the Internet.
  C. The prefixes sent with private AS numbers lack uniqueness, which can lead to a loss of connectivity.
  D. The prefixes sent with private AS numbers are sometimes tagged as invalid on the Internet.
  C. The prefixes sent with private AS numbers lack uniqueness, which can lead to a loss of connectivity.

  ---

  Private AS numbers are not meant to be used for global Internet BGP routing, as they are assigned locally and can be used by any organization. They are meant to enable BGP within a enterprise or VPN, but since these numbers can be used by any organization they are not unique and could cause connectivity loss if leaked to the Internet.

• Question 282:

  Which two hashing algorithms can be used when configuring SNMPv3? (Choose two.)

  A. MD5
  B. SHA-1
  C. Blowfish
  D. DES
  E. AES
  F. SSL
  A. MD5
  B. SHA-1

  ---

  Note that SNMPv3 does not send passwords in clear-text and uses hash-based authentication with either MD5 or SHA1 functions (HMAC authentication ?the packet conted is hashed along with authentication key to produce the authentication string).

  Reference: http://blog.ine.com/2008/07/19/snmpv3-tutorial/

• Question 283:

  Which three statements about RIP timers are true? (Choose three.)

  A. The default update timer is 30 seconds.
  B. The default invalid timer is 180 seconds.
  C. The default holddown timer is 180 seconds.
  D. The default flush timer is 60 seconds.
  E. The default scan timer is 60 seconds.
  F. The default hello timer is 5 seconds.
  A. The default update timer is 30 seconds.
  B. The default invalid timer is 180 seconds.
  C. The default holddown timer is 180 seconds.

  ---

  The routing information protocol uses the following timers as part of its operation: Update Timer Invalid Timer Flush Timer Holddown Timer Update Timer The update timer controls the interval between two gratuitous Response Message. By default the value is 30 seconds. The response message is broadcast to all its RIP enabled interface. Invalid Timer The invalid timer specifies how long a routing entry can be in the routing table without being updated. This is also called as expiration Timer. By default, the value is 180 seconds. After the timer expires the hop count of the routing entry will be set to 16, marking the destination as unreachable. Flush Timer The flush timer controls the time between the route is invalidated or marked as unreachable and removal of entry from the routing table. By default the value is 240 seconds. This is 60 seconds longer than Invalid timer. So for 60 seconds the router will be advertising about this unreachable route to all its neighbors. This timer must be set to a higher value than the invalid timer. Hold-down Timer The hold-down timer is started per route entry, when the hop count is changing from lower value to higher value. This allows the route to get stabilized. During this time no update can be done to that routing entry. This is not part of the RFC 1058. This is Cisco's implementation. The default value of this timer is 180 seconds.

  Reference: http://en.wikipedia.org/wiki/Routing_Information_Protocol#Timers

• Question 284:

  What is the function of NSF?

  A. forward traffic simultaneously using both supervisors
  B. forward traffic based on Cisco Express Forwarding
  C. provide automatic failover to back up supervisor in VSS mode
  D. provide nonstop forwarding in the event of failure of one of the member supervisors
  D. provide nonstop forwarding in the event of failure of one of the member supervisors

• Question 285:

  Which two features does the show ipv6 snooping features command show information about? (Choose two.)

  A. RA guard
  B. DHCP guard
  C. ND inspection
  D. source guard
  A. RA guard
  C. ND inspection

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  The show ipv6 snooping features command displays the first-hop features that are configured on the router. Examples The following example shows that both IPv6 NDP inspection and IPv6 RA guard are configured on the router: Router# show ipv6 snooping features Feature name priority state RA guard 100 READY NDP inspection 20 READY

  Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/ipv6/command/ipv6-cr- book/ipv6-s5.html

• Question 286:

  An access switch at a remote location is connected to the spanning-tree root with redundant uplinks. A network engineer notices that there are issues with the physical cabling of the current root port. The engineer decides to force the secondary link to be the desired forwarding root port. Which action accomplishes this task?

  A. Adjust the secondary link to have a lower priority than the primary link.
  B. Change the link type to point-to-point.
  C. Apply a BPDU filter on the primary interface of the remote switches.
  D. Enable Rapid Spanning Tree to converge using the secondary link.
  A. Adjust the secondary link to have a lower priority than the primary link.

• Question 287:

  Refer to the exhibit.

  

  Which three statements about the device with this configuration are true? (Choose three.)

  A. Multiple AFIs are configured on the device.
  B. The authentication on 172.16.129.7 is configured incorrectly.
  C. The device is configured to support MPLS VPNs.
  D. This device is configured with a single AFI.
  E. The authentication on 172.16.129.4 is configured incorrectly.
  F. The device is configured to support L2VPNs.
  A. Multiple AFIs are configured on the device.
  B. The authentication on 172.16.129.7 is configured incorrectly.
  C. The device is configured to support MPLS VPNs.

• Question 288:

  A floating static route appears in the routing table of an interface even when the interface is unusable.

  Which action can you take to correct the problem?

  A. Remove the permanent option from the static route.
  B. Correct the administrative distance.
  C. Configure the floating static route to point to another route in the routing table.
  D. Correct the DHCP-provided route on the DHCP server.
  A. Remove the permanent option from the static route.

• Question 289:

  Refer to the exhibit.

  

  R1 is able to reach only some of the subnets that R2 is advertising. Which two configuration changes can you make to ensure that R1 can reach all routes from R2? (Choose two.)

  A. Add an additional permit statement to the LOOPBACKS route map.
  B. Modify the LOOPBACKS access list to include all loopback subnets.
  C. Add an additional statement in the LOOPBACKS route map to match both Level 1 and Level 2 circuits.
  D. Add an additional statement in the LOOPBACKS route map to match the R1 CLNS address.
  E. Configure the interfaces between R1 and R2 with a Level 1 IS-IS circuit.
  F. Configure the interfaces between R1 and R2 with a Level 2 IS-IS circuit.
  A. Add an additional permit statement to the LOOPBACKS route map.
  B. Modify the LOOPBACKS access list to include all loopback subnets.

  ---

  In this example, the access list is using a 0.0.3.255 wildcard mask, so only the loopback IP's of 172.16.0.0 ?172.16.3.255 will be included. We need to add another statement to allow loopback 4 to be advertised, or modify the wildcard mask to include them all.

• Question 290:

  DRAG DROP

  Drag and drop Layer 2 QoS Commands on the left to the corresponding functions on the right.

  Select and Place: