Cisco 200-120 Online Practice Questions and Exam Preparation

Cisco 200-120 Online Questions & Answers

• Question 1:

  Which command displays CPU utilization?

  A. show protocols
  B. show process
  C. show system
  D. show version
  B. show process

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  The "show process" (in fact, the full command is "show processes") command gives us lots of information about each process but in fact it is not easy to read. Below shows the output of this command (some next pages are omitted).

  

  A more friendly way to check the CPU utilization is the command "show processes cpu history", in which the total CPU usage on the router over a period of time: one minute, one hour, and 72 hours are clearly shown:

  

  +

  The Y-axis of the graph is the CPU utilization.

  +

  The X-axis of the graph is the increment within the period displayed in the graph.

  For example, from the last graph (last 72 hours) we learn that the highest CPU utilization within 72 hours is 37% about six hours ago.

• Question 2:

  A network engineer wants to allow a temporary entry for a remote user with a specific username and password so that the user can access the entire network over the Internet. Which ACL can be used?

  A. standard
  B. extended
  C. dynamic
  D. reflexive
  C. dynamic

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  We can use a dynamic access list to authenticate a remote user with a specific username and password. The authentication process is done by the router or a central access server such as a TACACS+ or RADIUS server. The configuration of dynamic ACL can be read here: http://www.cisco.com/en/US/tech/tk583/tk822/technologies_tech_note09186a0080094524.shtml

• Question 3:

  An administrator must assign static IP addresses to the servers in a network. For network 192.168.20.24/29, the router is assigned the first usable host address while the sales server is given the last usable host address. Which of the following should be entered into the IP properties box for the sales server?

  A. IP address: 192.168.20.14 Subnet Mask: 255.255.255.248 Default Gateway: 192.168.20.9
  B. IP address: 192.168.20.254 Subnet Mask: 255.255.255.0 Default Gateway: 192.168.20.1
  C. IP address: 192.168.20.30 Subnet Mask: 255.255.255.248 Default Gateway: 192.168.20.25
  D. IP address: 192.168.20.30 Subnet Mask: 255.255.255.240 Default Gateway: 192.168.20.17
  E. IP address: 192.168.20.30 Subnet Mask: 255.255.255.240 Default Gateway: 192.168.20.25
  C. IP address: 192.168.20.30 Subnet Mask: 255.255.255.248 Default Gateway: 192.168.20.25

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  For the 192.168.20.24/29 network, the usable hosts are 192.168.24.25 (router) ?192.168.24.30 (used for the sales server).

• Question 4:

  Refer to the exhibit.

  

  The speed of all serial links is E1 and the speed of all Ethernet links is 100 Mb/s. A static route will be established on the Manchester router to direct traffic toward the Internet over the most direct path available. What configuration on the Manchester router will establish a route toward the Internet for traffic that originates from workstations on the Manchester LAN?

  A. ip route 0.0.0.0 255.255.255.0 172.16.100.2
  B. ip route 0.0.0.0 0.0.0.0 128.107.1.1
  C. ip route 0.0.0.0 255.255.255.252 128.107.1.1
  D. ip route 0.0.0.0 0.0.0.0 172.16.100.1
  E. ip route 0.0.0.0 0.0.0.0 172.16.100.2
  F. ip route 0.0.0.0 255.255.255.255 172.16.100.2
  E. ip route 0.0.0.0 0.0.0.0 172.16.100.2

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  We use default routing to send packets with a remote destination network not in the routing table to the next-hop router. You should generally only use default routing on stub networks--those with only one exit path out of the network.

  According to exhibit, all traffic towards Internet that originates from workstations should forward to Router R1.

  Syntax for default route is:

  ip route .

• Question 5:

  What are two benefits of using a single OSPF area network design? (Choose two.)

  A. It is less CPU intensive for routers in the single area.
  B. It reduces the types of LSAs that are generated.
  C. It removes the need for virtual links.
  D. It increases LSA response times.
  E. It reduces the number of required OSPF neighbor adjacencies.
  B. It reduces the types of LSAs that are generated.
  C. It removes the need for virtual links.

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  OSPF uses a LSDB (link state database) and fills this with LSAs (link state advertisement). The link types are as follows:

  LSA Type 1: Router LSA

  

  LSA Type 2: Network LSA LSA Type 3: Summary LSA

  

  

  LSA Type 4: Summary ASBR LSA

  

  LSA Type 5: Autonomous system external LSA

  

  LSA Type 6: Multicast OSPF LSA

  

  LSA Type 7: Not-so-stubby area LSA

  

  LSA Type 8: External attribute LSA for BGP

  

  If all routers are in the same area, then many of these LSA types (Summary ASBR LSA, external LSA, etc) will not be used and will not be generated by any router.

  All areas in an Open Shortest Path First (OSPF) autonomous system must be physically connected to the backbone area (Area 0). In some cases, where this is not possible, you can use a virtual link to connect to the backbone through a non- backbone area. You can also use virtual links to connect two parts of a partitioned backbone through a non-backbone area. The area through which you configure the virtual link, known as a transit area, must have full routing information. The transit area cannot be a stub area. Virtual links are not ideal and should really only be used for temporary network solutions or migrations. However, if all locations are in a single OSPF area this is not needed.

• Question 6:

  Refer to the exhibit.

  

  The technician wants to upload a new IOS in the router while keeping the existing IOS. What is the maximum size of an IOS file that could be loaded if the original IOS is also kept in flash?

  A. 3 MB
  B. 4 MB
  C. 5 MB
  D. 7 MB
  E. 8 MB
  B. 4 MB

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  In this example, there are a total of 8 MB, but 3.8 are being used already, so another file as large as 4MB can be loaded in addition to the original file.

• Question 7:

  Which of the following describes the roles of devices in a WAN? (Choose three.)

  A. A CSU/DSU terminates a digital local loop.
  B. A modem terminates a digital local loop.
  C. A CSU/DSU terminates an analog local loop.
  D. A modem terminates an analog local loop.
  E. A router is commonly considered a DTE device.
  F. A router is commonly considered a DCE device.
  A. A CSU/DSU terminates a digital local loop.
  D. A modem terminates an analog local loop.
  E. A router is commonly considered a DTE device.

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  The idea behind a WAN is to be able to connect two DTE networks together through a DCE network. The network's DCE device (includes CSU/DSU) provides clocking to the DTE-connected interface (the router's serial interface).

  

  A modem modulates outgoing digital signals from a computer or other digital device to analog signals for a conventional copper twisted pair telephone line and demodulates the incoming analog signal and converts it to a digital signal for the digital device. A CSU/DSU is used between two digital lines For more explanation of answer D, in telephony the local loop (also referred to as a subscriber line) is the physical link or circuit that connects from the demarcation point of the customer premises to the edge of the carrier or telecommunications service provider's network. Therefore a modem terminates an analog local loop is correct.

  

• Question 8:

  What are three approaches that are used when migrating from an IPv4 addressing scheme to an IPv6 scheme. (Choose three.)

  A. enable dual-stack routing
  B. configure IPv6 directly
  C. configure IPv4 tunnels between IPv6 islands
  D. use proxying and translation to translate IPv6 packets into IPv4 packets
  E. statically map IPv4 addresses to IPv6 addresses
  F. use DHCPv6 to map IPv4 addresses to IPv6 addresses
  A. enable dual-stack routing
  C. configure IPv4 tunnels between IPv6 islands
  D. use proxying and translation to translate IPv6 packets into IPv4 packets

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  Several methods are used terms of migration including tunneling, translators, and dual stack. Tunnels are used to carry one protocol inside another, while translators simply translate IPv6 packets into IPv4 packets. Dual stack uses a combination of both native IPv4 and IPv6. With dual stack, devices are able to run IPv4 and IPv6 together and if IPv6 communication is possible that is the preferred protocol. Hosts can simultaneously reach IPv4 and IPv6 content.

• Question 9:

  Which Cisco Catalyst feature automatically disables the port in an operational PortFast upon receipt of a BPDU?

  A. BackboneFast
  B. UplinkFast
  C. Root Guard
  D. BPDU Guard
  E. BPDU Filter
  D. BPDU Guard

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  We only enable PortFast feature on access ports (ports connected to end stations). But if someone does not know he can accidentally plug that port to another switch and a loop may occur when BPDUs are being transmitted and received on

  these ports.

  With BPDU Guard, when a PortFast receives a BPDU, it will be shut down to prevent a loop.

• Question 10:

  In GLBP, which router will respond to client ARP requests?

  A. The active virtual gateway will reply with one of four possible virtual MAC addresses.
  B. All GLBP member routers will reply in round-robin fashion.
  C. The active virtual gateway will reply with its own hardware MAC address.
  D. The GLBP member routers will reply with one of four possible burned in hardware addresses.
  A. The active virtual gateway will reply with one of four possible virtual MAC addresses.

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  One disadvantage of HSRP and VRRP is that only one router is in use, other routers must wait for the primary to fail because they can be used. However, Gateway Load Balancing Protocol (GLBP) can use of up to four routers simultaneously. In GLBP, there is still only one virtual IP address but each router has a different virtual MAC address. First a GLBP group must elect an Active Virtual Gateway (AVG). The AVG is responsible for replying ARP requests from hosts/clients. It replies with different virtual MAC addresses that correspond to different routers (known as Active Virtual Forwarders ?AVFs) so that clients can send traffic to different routers in that GLBP group (load sharing).