Cisco CCNA 200-301 Questions & Answers

• Question 601:

  What causes a port to be placed in the err-disabled state?

  A. nothing plugged into the port

  B. link flapping

  C. latency

  D. shutdown command issued on the port

  Correct Answer: B

  There are various reasons for the interface to go into errdisable. The reason can be:

  1.

  Duplex mismatch

  2.

  Port channel misconfiguration

  3.

  BPDU guard violation

  4.

  UniDirectional Link Detection (UDLD) condition

  5.

  Late-collision detection

  6.

  Link-flap detection

  7.

  Security violation

  8.

  Port Aggregation Protocol (PAgP) flap

  9.

  Layer 2 Tunneling Protocol (L2TP) guard 10.DHCP snooping rate-limit 11.Incorrect GBIC / Small Form-Factor Pluggable (SFP) module or cable 12.Address Resolution Protocol (ARP) inspection

  https://www.cisco.com/c/en/us/support/docs/lan-switching/spanning-tree-protocol/69980-errdisable-recovery.html#anc8

• Question 602:

  What causes a port to be placed in the err-disabled state?

  A. latency

  B. port security violation

  C. shutdown command issued on the port

  D. nothing plugged into the port

  Correct Answer: B

  This mode is the default violation mode; when in this mode, the switch will automatically force the switchport into an error disabled (err-disable) state when a violation occurs. While in this state, the switchport forwards no traffic. The switchport can be brought out of this error disabled state by issuing the errdisable recovery cause CLI command or by disabling and reenabling the switchport.

• Question 603:

  What is the purpose of a southbound API in a control based networking architecture?

  A. Facilities communication between the controller and the applications

  B. Facilities communication between the controller and the networking hardware

  C. allows application developers to interact with the network

  D. integrates a controller with other automation and orchestration tools.

  Correct Answer: B

  The Southbound Interface

  In a controller-based network architecture, the controller needs to communicate to the networking devices. In most network drawings and architecture drawings, those network devices typically sit below the controller, as shown in Figure 16-5.

  There is an interface between the controller and those devices, and given its location at the bottom part of drawings, the interface came to be known as the southbound interface, or SBI, as labeled in Figure 16-5.

  

• Question 604:

  Which switch technology establishes a network connection immediately when it is plugged in?

  A. PortFast

  B. BPDU guard

  C. UplinkFast

  D. BackboneFast

  Correct Answer: A

  enable spanning-tree uplinkfast. This is a global command, you can't configure it on the interface level.

  When uplinkfast is enabled a non-designated port will go to forwarding state immediately if the root port fails. Instead of 30 seconds downtime connectivity is restored immediately.

• Question 605:

  What is a benefit of VRRP?

  A. It provides traffic load balancing to destinations that are more than two hops from the source.

  B. It provides the default gateway redundancy on a LAN using two or more routers.

  C. It allows neighbors to share routing table information between each other.

  D. It prevents loops in a Layer 2 LAN by forwarding all traffic to a root bridge, which then makes the final forwarding decision.

  Correct Answer: B

  Reference: https://www.cisco.com/c/en/us/td/docs/routers/crs/software/crs_r4-0/addr_serv/configuration/guide/ic40crs1book_chapter10.html

• Question 606:

  Which protocol does an IPv4 host use to obtain a dynamically assigned IP address?

  A. ARP

  B. DHCP

  C. CDP

  D. DNS

  Correct Answer: B

  https://www.geeksforgeeks.org/how-dhcp-server-dynamically-assigns-ip-address-to-a-host/#:~:text=DHCP%20is%20an%20abbreviation%20for,subnet%20mask%20and%20gateway%20ad dress.

• Question 607:

  Refer to the exhibit. An access list is required to permit traffic from any host on interface G0/0 and deny traffic from interface G/0/1. Which access list must be applied?

  

  

  A. Option A

  B. Option B

  C. Option C

  D. Option D

  Correct Answer: A

• Question 608:

  How does a switch process a frame received on Fa0/1 with the destination MAC address of 0e38.7363.657b when the table is missing the address?

  A. lt drops the frame immediately.

  B. It forwards the frame back out of interface Fa0/1.

  C. It floods the frame to all interfaces except Fa0/1.

  D. It holds the frame until the MAC address timer expires and then drops the frame.

  Correct Answer: C

• Question 609:

  Which condition must be met before an NMS handles an SNMP trap from an agent?

  A. The NMS software must be loaded with the MIB associated with the trap.

  B. The NMS must be configured on the same router as the SNMP agent

  C. The NMS must receive a trap and an inform message from the SNMP agent within a configured interval

  D. The NMS must receive the same trap from two different SNMP agents to verify that it is reliable.

  Correct Answer: A

• Question 610:

  Why does a switch flood a frame to all ports?

  A. The frame has zero destination MAC addresses.

  B. The source MAC address of the frame is unknown

  C. The source and destination MAC addresses of the frame are the same

  D. The destination MAC address of the frame is unknown.

  Correct Answer: D