Cisco 200-120 Online Practice Questions and Exam Preparation

Cisco 200-120 Online Questions & Answers

• Question 121:

  Which two states are the port states when RSTP has converged? (Choose two.)

  A. discarding
  B. listening
  C. learning
  D. forwarding
  E. disabled
  A. discarding
  D. forwarding

  ---

  There are only three port states left in RSTP that correspond to the three possible operational states. The 802.1D disabled, blocking, and listening states are merged into a unique 802.1w discarding state.

  

  Reference: http://www.cisco.com/en/US/tech/tk389/tk621/technologies_white_paper09186a0080094cfa.shtml#states

• Question 122:

  Scenario

  Refer to the topology. Your company has connected the routers R1, R2, and R3 with serial links. R2 and R3 are connected to the switches SW1 and SW2, respectively. SW1 and SW2 are also connected to the routers R4 and R5.

  The EIGRP routing protocol is configured.

  You are required to troubleshoot and resolve the EIGRP issues between the various routers.

  Use the appropriate show commands to troubleshoot the issues.

  

  

  

  Study the following output taken on R1:

  R1# Ping 10.5.5.55 source 10.1.1.1

  Type escape sequence to abort.

  Sending 5, 100-byte ICMP Echos to 10.5.5.55, timeout is 2 seconds:

  Packet sent with a source address of 10.1.1.1

  .......

  Success rate is 0 percent (0/5)

  Why are the pings failing?

  A. The network statement is missing on R5.
  B. The loopback interface is shut down on R5.
  C. The network statement is missing on R1.
  D. The IP address that is configured on the Lo1 interface on R5 is incorrect.
  C. The network statement is missing on R1.

  ---

  R5 does not have a route to the 10.1.1.1 network, which is the loopback0 IP address of R1. When looking at the EIGRP configuration on R1, we see that the 10.1.1.1 network statement is missing on R1.

  

• Question 123:

  What is the default maximum number of equal-cost paths that can be placed into the routing table of a Cisco OSPF router?

  A. 2
  B. 8
  C. 16
  D. unlimited
  B. 8

  ---

  maximum-paths (OSPF)

  To control the maximum number of parallel routes that Open Shortest Path First (OSPF) can support, use the maximum-paths command.

  Syntax Description

  

  Command Default 8 paths

• Question 124:

  What is the result of issuing the frame-relay map ip 192.168.1.2 202 broadcast command?

  A. defines the destination IP address that is used in all broadcast packets on DCLI 202
  B. defines the source IP address that is used in all broadcast packets on DCLI 202
  C. defines the DLCI on which packets from the 192.168.1.2 IP address are received
  D. defines the DLCI that is used for all packets that are sent to the 192.168.1.2 IP address
  D. defines the DLCI that is used for all packets that are sent to the 192.168.1.2 IP address

  ---

  This command identifies the DLCI that should be used for all packets destined to the 192.168.1.2 address. In this case, DLCI 202 should be used.

• Question 125:

  Which three statements about Syslog utilization are true? (Choose three.)

  A. Utilizing Syslog improves network performance.
  B. The Syslog server automatically notifies the network administrator of network problems.
  C. A Syslog server provides the storage space necessary to store log files without using router disk space.
  D. There are more Syslog messages available within Cisco IOS than there are comparable SNMP trap messages.
  E. Enabling Syslog on a router automatically enables NTP for accurate time stamping.
  F. A Syslog server helps in aggregation of logs and alerts.
  C. A Syslog server provides the storage space necessary to store log files without using router disk space.
  D. There are more Syslog messages available within Cisco IOS than there are comparable SNMP trap messages.
  F. A Syslog server helps in aggregation of logs and alerts.

  ---

  The Syslog sender sends a small (less than 1KB) text message to the Syslog receiver. The Syslog receiver is commonly called "syslogd," "Syslog daemon," or "Syslog server." Syslog messages can be sent via UDP (port 514) and/or TCP (typically, port 5000). While there are some exceptions, such as SSL wrappers, this data is typically sent in clear text over the network. A Syslog server provides the storage space necessary to store log files without using router disk space. In general, there are significantly more Syslog messages available within IOS as compared to SNMP Trap messages. For example, a Cisco Catalyst 6500 switch running Cisco IOS Software Release 12.2(18)SXF contains about 90 SNMP trap notification messages, but has more than 6000 Syslog event messages. System logging is a method of collecting messages from devices to a server running a syslog daemon. Logging to a central syslog server helps in aggregation of logs and alerts. Cisco devices can send their log messages to a UNIX-style syslog service. A syslog service accepts messages and stores them in files, or prints them according to a simple configuration file.

  Reference: http://www.cisco.com/c/en/us/products/collateral/services/high-availability/white_paper_c11-557812.html

• Question 126:

  Which statement about access lists that are applied to an interface is true?

  A. You can place as many access lists as you want on any interface.
  B. You can apply only one access list on any interface.
  C. You can configure one access list, per direction, per Layer 3 protocol.
  D. You can apply multiple access lists with the same protocol or in different directions.
  C. You can configure one access list, per direction, per Layer 3 protocol.

  ---

  We can have only 1 access list per protocol, per direction and per interface. It means:

  +

  We cannot have 2 inbound access lists on an interface

  +

  We can have 1 inbound and 1 outbound access list on an interface

• Question 127:

  Which two commands can be used to verify a trunk link configuration status on a given Cisco switch interface? (Choose two.)

  A. show interface trunk
  B. show interface interface
  C. show ip interface brief
  D. show interface vlan
  E. show interface switchport
  A. show interface trunk
  E. show interface switchport

  ---

  Example output from these two commands: SW3#show interface trunk Port Mode Encapsulation Status Native vlan Fa0/19 auto n-802.1q trunking 1 Fa0/20 auto n-802.1q trunking 1 Fa0/21 auto n-802.1q trunking 1 Fa0/22 auto n-802.1q trunking 1 Port Vlans allowed on trunk Fa0/19 1-4094 Fa0/20 1-4094 Fa0/21 1-4094 Fa0/22 1-4094

  SW1#show interface fast 0/2 switchport Name: Fa0/2 Switchport: Enabled Administrative Mode: dynamic desirable Operational Mode: down Administrative Trunking Encapsulation: dot1q Negotiation of TrunkinG. On Access Mode VLAN: 1 (default) Trunking Native Mode VLAN: 1 (default) Voice VLAN: none

• Question 128:

  Which command would you use on a Cisco router to verify the Layer 3 path to a host?

  A. tracert address
  B. traceroute address
  C. telnet address
  D. ssh address
  B. traceroute address

  ---

  In computing, traceroute is a computer network diagnostic tool for displaying the route (path) and measuring transit delays of packets across an Internet Protocol (IP) network. The history of the route is recorded as the round-trip times of the packets received from each successive host (remote node) in the route (path); the sum of the mean times in each hop indicates the total time spent to establish the connection. Traceroute proceeds unless all (three) sent packets are lost more than twice, then the connection is lost and the route cannot be evaluated. Ping, on the other hand, only computes the final round-trip times from the destination point.

• Question 129:

  Refer to the exhibit.

  

  Each of these four switches has been configured with a hostname, as well as being configured to run RSTP. No other configuration changes have been made. Which three of these show the correct RSTP port roles for the indicated switches and interfaces? (Choose three.)

  A. SwitchA, Fa0/2, designated
  B. SwitchA, Fa0/1, root
  C. SwitchB, Gi0/2, root
  D. SwitchB, Gi0/1, designated
  E. SwitchC, Fa0/2, root
  F. SwitchD, Gi0/2, root
  A. SwitchA, Fa0/2, designated
  B. SwitchA, Fa0/1, root
  F. SwitchD, Gi0/2, root

  ---

  The question says "no other configuration changes have been made" so we can understand these switches have the same bridge priority. Switch C has lowest MAC address so it will become root bridge and 2 of its ports (Fa0/1 and Fa0/2) will

  be designated ports.

  Because SwitchC is the root bridge so the 2 ports nearest SwitchC on SwitchA (Fa0/1) and SwitchD (Gi0/2) will be root ports.

  Now we come to the most difficult part of this question: SwitchB must have a root port so which port will it choose? To answer this question we need to know about STP cost and port cost. In general, "cost" is calculated based on bandwidth of

  the link. The higher the bandwidth on a link, the lower the value of its cost. Below are the cost values you should memorize:

  

  SwitchB will choose the interface with lower cost to the root bridge as the root port so we must calculate the cost on interface Gi0/1 and Gi0/2 of SwitchB to the root bridge. This can be calculated from the "cost to the root bridge" of each switch because a switch always advertises its cost to the root bridge in its BPDU. The receiving switch will add its local port cost value to the cost in the BPDU. One more thing to notice is that a root bridge always advertises the cost to the root bridge (itself) with an initial value of 0. Now let's have a look at the topology again SwitchC advertises its cost to the root bridge with a value of 0. Switch D adds 4 (the cost value of 1Gbps link) and advertises this value (4) to SwitchB. SwitchB adds another 4 and learns that it can reach SwitchC via Gi0/1 port with a total cost of 8. The same process happens for SwitchA and SwitchB learns that it can reach SwitchC via Gi0/2 with a total cost of 23 -> Switch B chooses Gi0/1 as its root port ->. Now our last task is to identify the port roles of the ports between SwitchA and SwitchB. It is rather easy as the MAC address of SwitchA is lower than that of SwitchB so Fa0/2 of SwitchA will be designated port while Gi0/2 of SwitchB will be alternative port.

  

  Below summaries all the port roles of these switches:

  

  +

  DP: Designated Port (forwarding state)

  +

  RP: Root Port (forwarding state)

  +

  AP: Alternative Port (blocking state)

• Question 130:

  At which layer of the OSI model is RSTP used to prevent loops?

  A. physical
  B. data link
  C. network
  D. transport
  B. data link

  ---

  RSTP and STP operate on switches and are based on the exchange of Bridge Protocol Data Units (BPDUs) between switches. One of the most important fields in BPDUs is the Bridge Priority in which the MAC address is used to elect the Root Bridge -> RSTP operates at Layer 2 ?Data Link layer >;.