Cisco CCNP Enterprise 350-401 Questions & Answers

• Question 391:

  When reason could cause an OSPF neighborship to be in the EXSTART/EXCHANGE state?

  A. Mismatched OSPF network type

  B. Mismatched areas

  C. Mismatched MTU size

  D. Mismatched OSPF link costs

  Correct Answer: C

  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) Neighbors Stuck in Exstart/Exchange

  State

  the problem occurs most frequently when attempting to run OSPF between a Cisco router and another vendor's router. The problem occurs when the maximum transmission unit (MTU) settings for neighboring router interfaces don't match. If

  the router with the higher MTU sends a packet larger that the MTU set on the neighboring router, the neighboring router ignores the packet.

  Reference: https://www.cisco.com/c/en/us/support/docs/ip/open-shortest-path-first-ospf/13684-12.html#neighbors

• Question 392:

  Which feature must be configured to allow packet capture over Layer 3 infrastructure'?

  A. VSPAN

  B. IPSPAN

  C. RSPAN

  D. ERSPAN

  Correct Answer: D

  Encapsulated remote SPAN (ERSPAN): encapsulated Remote SPAN (ERSPAN), as the name says, brings generic routing encapsulation (GRE) for all captured traffic and allows it to be extended across Layer 3 domains.

  Reference: https://community.cisco.com/t5/networking-documents/understanding-span-rspan-and-erspan/ta-p/3144951

• Question 393:

  What is a benefit of deploying an on-premises infrastructure versus a cloud infrastructure deployment?

  A. faster deployment times because additional infrastructure does not need to be purchased

  B. lower latency between systems that are physically located near each other

  C. less power and cooling resources needed to run infrastructure on-premises

  D. ability to quickly increase compute power without the need to install additional hardware

  Correct Answer: B

  The difference between on-premise and cloud is essentially where this hardware and software resides. On-premise means that a company keeps all of this IT environment onsite either managed by themselves or a third-party. Cloud means that it is housed offsite with someone else responsible for monitoring and maintaining it.

• Question 394:

  Which statement about route targets is true when using VRF-Lite?

  A. When BGP is configured, route targets are transmitted as BGP standard communities.

  B. Route targets control the import and export of routes into a customer routing table.

  C. Route targets allow customers to be assigned overlapping addresses.

  D. Route targets uniquely identify the customer routing table.

  Correct Answer: B

  Answer 'Route targets allow customers to be assigned overlapping addresses' and answer 'Route targets uniquely identify the customer routing table' are not correct as only route distinguisher (RD) identifies the customer routing table and

  "allows customers to be assigned overlapping addresses".

  Answer 'When BGP is configured, route targets are transmitted as BGP standard communities' is not correct as "When BGP is configured, route targets are transmitted as BGP extended communities"

• Question 395:

  Which statement about an RSPAN session configuration is true?

  A. A fitter mutt be configured for RSPAN Regions.

  B. Only one session can be configured at a time.

  C. A special VLAN type must be used as the RSPAN destination.

  D. Only incoming traffic can be monitored.

  Correct Answer: C

  in all participating switches -> This VLAN can be considered a special VLAN type -> Answer 'A special VLAN type must be used as the RSPAN destination' is correct.

  Reference: https://www.cisco.com/c/en/us/td/docs/switches/lan/catalyst3750x_3560x/software/r elease/12-2_55_se/configuration/guide/3750xscg/swspan.html

  We can configure multiple RSPAN sessions on a switch at a time, then continue configuring multiple RSPAN sessions on the other switch without any problem -> Answer 'Only one session can be configured at a time' is not correct. This is how to configure Remote SPAN (RSPAN) feature on two switches. Traffic on FastEthernet0/1 of Switch 1 will be sent to Fa0/10 of Switch2 via VLAN 40.

  +

  Configure on both switches Switch1,2(config)#vlan 40 Switch1,2(config-vlan)#remote-span

  +

  Configure on Switch1 Switch1(config)# monitor session 1 source interface FastEthernet 0/1 Switch1(config)# monitor session 1 destination remote vlan 40 + Configure on Switch2 Switch2(config)#monitor session 5 source remote vlan 40 Switch2(config)# monitor session 5 destination interface FastEthernet 0/10

• Question 396:

  Which First Hop Redundancy Protocol maximizes uplink utilization and minimizes the amount of configuration that is necessary?

  A. GLBP

  B. HSRP v2

  C. VRRP

  D. HSRP v1

  Correct Answer: A

  only GLBP can maximize utilzation of links by being ACTIVE/ACTIVE while all others are ACTIVE/STANDBY/LISTENING

  NOTE!!!! there is NO MHSRP only HSRP v1 and 2.

• Question 397:

  Which statements are used for error handling in Python?

  A. try/catch

  B. try/except

  C. block/rescue

  D. catch/release

  Correct Answer: B

  The words "try" and "except" are Python keywords and are used to catch exceptions.

  For example:

  try:

  print 1/0

  except ZeroDivisionError:

  print 'Error! We cannot divide by zero!!!'

• Question 398:

  A local router shows an EBGP neighbor in the Active state. Which statement is true about the local router?

  A. The local router has active prefix in the forwarding table from the neighboring router.

  B. The local router has BGP passive mode configured for the neighboring router.

  C. The local router is attempting to open a TCP session with the neighboring router.

  D. The local router is receiving prefixes from the neighboring router and adding them in RIB-IN.

  Correct Answer: C

  The BGP session may report in the following states 1 Idle: the initial state of a BGP connection. In this state, the BGP speaker is waiting for a BGP start event, generally either the establishment of a TCP connection or the re-establishment of a previous connection. Once the connection is established, BGP moves to the next state. 2 Connect: In this state, BGP is waiting for the TCP connection to be formed. If the TCP connection completes, BGP will move to the Open Sent stage; if the connection cannot complete, BGP goes to Active 3 Active: In the Active state, the BGP speaker is attempting to initiate a TCP session with the BGP speaker it wants to peer with. If this can be done, the BGP state goes to Open Sent state. 4 Open Sent: the BGP speaker is waiting to receive an OPEN message from the remote BGP speaker 5 Open Confirm: Once the BGP speaker receives the OPEN message and no error is detected, the BGP speaker sends a KEEPALIVE message to the remote BGP speaker 6 Established: All of the neighbor negotiations are complete. You will see a number, which tells us the number of prefixes the router has received from a neighbor or peer group.

• Question 399:

  Which standard access control entry permits from odd-numbered hosts in the 10.0.0.0/24 subnet?

  A. Permit 10.0.0.0.0.0.0.1

  B. Permit 10.0.0.1.0.0.0.0

  C. Permit 10.0.0.1.0.0.0.254

  D. Permit 10.0.0.0.255.255.255.254

  Correct Answer: C

  Remember, for the wildcard mask, 1s are I DON'T CARE, and 0s are I CARE. So now let's analyze a simple ACL:

  access-list 1 permit 172.23.16.0 0.0.15.255

  Two first octets are all 0's meaning that we care about the network 172.23.x.x. The third octet of the wildcard mask, 15 (0000 1111 in binary), means that we care about first 4 bits but don't care about last 4 bits so we allow the third octet in the

  form of 0001xxxx (minimum:00010000 = 16; maximum: 0001111 = 31).

  

  The fourth octet is 255 (all 1 bits) that means I don't care. Therefore network 172.23.16.0 0.0.15.255 ranges from 172.23.16.0 to 172.23.31.255. Now let's consider the wildcard mask of 0.0.0.254 (four octet: 254 = 1111 1110) which means we

  only care the last bit. Therefore if the last bit of the IP address is a "1" (0000 0001) then only odd numbers are allowed. If the last bit of the IP address is a "0" (0000 0000) then only even numbers are allowed.

  Note: In binary, odd numbers are always end with a "1" while even numbers are always end with a "0".

  Therefore in this question, only the statement "permit 10.0.0.1 0.0.0.254" will allow all oddnumbered

  hosts in the 10.0.0.0/24 subnet.

• Question 400:

  Based on this interface configuration, what is the expected state of OSPF adjacency?

  

  A. Full on both routers

  B. not established

  C. 2WAY/DROTHER on both routers

  D. FULL/BDR on R1 and FULL/BDR on R2

  Correct Answer: B

  On Ethernet interfaces the OSPF hello intervl is 10 second by default so in this case there would be a Hello interval mismatch -> the OSPF adjacency would not be established.