200-125 Exam - CCNA Cisco Certified Network Associate CCNA (v3.0)

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Q1.  - (Topic 7)

What are three reasons to collect Netflow data on a company network? (Choose three.)

A. To identify applications causing congestion.

B. To authorize user network access.

C. To report and alert link up / down instances.

D. To diagnose slow network performance, bandwidth hogs, and bandwidth utilization.

E. To detect suboptimal routing in the network.

F. To confirm the appropriate amount of bandwidth that has been allocated to each Class of Service.

Answer: A,D,F

Explanation:

NetFlow facilitates solutions to many common problems encountered by IT professionals.

+ Analyze new applications and their network impact

Identify new application network loads such as VoIP or remote site additions.

+ Reduction in peak WAN traffic

Use NetFlow statistics to measure WAN traffic improvement from application-policy changes; understand who is utilizing the network and the network top talkers.

+ Troubleshooting and understanding network pain points

Diagnose slow network performance, bandwidth hogs and bandwidth utilization quickly with command line interface or reporting tools. -> D is correct.

+ Detection of unauthorized WAN traffic

Avoid costly upgrades by identifying the applications causing congestion. -> A is correct.

+ Security and anomaly detection

NetFlow can be used for anomaly detection and worm diagnosis along with applications such as Cisco CS-Mars.

+ Validation of QoS parameters

Confirm that appropriate bandwidth has been allocated to each Class of Service (CoS) and that no CoS is over- or under-subscribed.-> F is correct.

Q2.  - (Topic 8)

Which command can you execute to set the user inactivity timer to 10 seconds?

A. SW1(config-line)#exec-timeout 0 10

B. SW1(config-line)#exec-timeout 10

C. SW1(config-line)#absolute-timeout 0 10

D. SW1(config-line)#absolute-timeout 10

Answer: A

Q3.  - (Topic 8)

Why did Branch1 router lose WAN connectivity with R1 router?

A. The IP address is misconfigured on PPP multilink interface on the Branch1 router.

B. The PPP multilink group is misconfigured on the £ranch1 serial interfaces.

C. The PPP multilink group is misconfigured on the R1 serial interfaces.

D. The Branch1 serial interfaces are placed in a shutdown condition.

Answer: A

Q4.  - (Topic 5)

What is the default Syslog facility level?

A. local4

B. local5

C. local6

D. local7

Answer: D

Explanation:

By default, Cisco IOS devices, CatOS switches, and VPN 3000 Concentrators use facility local7 while Cisco PIX Firewalls use local4 to send syslog messages. Moreover, most Cisco devices provide options to change the facility level from their default value.

Reference: http://www.ciscopress.com/articles/article.asp?p=426638

Q5.  - (Topic 4)

Which two statistics appear in show frame-relay map output? (Choose two.)

A. the number of BECN packets that are received by the router

B. the value of the local DLCI

C. the number of FECN packets that are received by the router

D. the status of the PVC that is configured on the router

E. the IP address of the local router

Answer: B,D

Explanation:

Sample “show frame-relay map” output: R1#sh frame map

Serial0/0 (up): ip 10.4.4.1 dlci 401(0x191,0x6410), dynamic, broadcast,, status defined, active

Serial0/0 (up): ip 10.4.4.3 dlci 403(0x193,0x6430), dynamic, broadcast,, status defined, active

Serial0/0 (up): ip 10.4.4.4 dlci 401(0x191,0x6410), static, CISCO, status defined, active

Q6.  - (Topic 3)

What information does a router running a link-state protocol use to build and maintain its topological database? (Choose two.)

A. hello packets

B. SAP messages sent by other routers

C. LSAs from other routers

D. beacons received on point-to-point links

E. routing tables received from other link-state routers

F. TTL packets from designated routers

Answer: A,C

Explanation:

Neighbor discovery is the first step in getting a link state environment up and running. In keeping with the friendly neighbor terminology, a Hello protocol is used for this step. The protocol will define a Hello packet format and a procedure for exchanging the packets and processing the information the packets contain.

After the adjacencies are established, the routers may begin sending out LSAs. As the term flooding implies, the advertisements are sent to every neighbor. In turn, each received LSA

is copied and forwarded to every neighbor except the one that sent the LSA.

Q7.  - (Topic 5)

In a GLBP network, who is responsible for the ARP request?

A. AVF

B. AVG

C. Active Router

D. Standby Router

Answer: B

Explanation:

Members of a GLBP group elect one gateway to be the active virtual gateway (AVG) for that group. Other group members provide backup for the AVG in the event that the AVG becomes unavailable. The AVG assigns a virtual MAC address to each member of the GLBP group. Each gateway assumes responsibility for forwarding packets sent to the virtual MAC address assigned to it by the AVG. These gateways are known as active virtual forwarders (AVFs) for their virtual MAC address.

The AVG is responsible for answering Address Resolution Protocol (ARP) requests for the virtual IP address. Load sharing is achieved by the AVG replying to the ARP requests with different virtual MAC addresses.

Reference: http://www.cisco.com/en/US/docs/ios/12_2t/12_2t15/feature/guide/ft_glbp.html

Q8. CORRECT TEXT - (Topic 7)

The following have already been configured on the router:

✑ The basic router configuration

✑ The appropriate interfaces have been configured for NAT inside and NAT outside.

✑ The appropriate static routes have also been configured (since the company will be a stub network, no routing protocol will be required)

✑ All passwords have been temporarily set to “cisco”.

The task is to complete the NAT configuration using all IP addresses assigned by the ISP to provide Internet access for the hosts in the Weaver LAN. Functionality can be tested by clicking on the host provided for testing.

Configuration information:

router name – Weaver

inside global addresses – 198.18.184.105 - 198.18.184.110/29 inside local addresses - 192.168.100.17 – 192.168.100.30/28 number of inside hosts – 14

A network associate is configuring a router for the weaver company to provide internet access. The ISP has provided the company six public IP addresses of 198.18.184.105 198.18.184.110. The company has 14 hosts that need to access the internet simultaneously. The hosts in the company LAN have been assigned private space addresses in the range of 192.168.100.17 – 192.168.100.30.

Answer:  

The company has 14 hosts that need to access the internet simultaneously but we just have 6 public IP addresses from 198.18.184.105 to 198.18.184.110/29. Therefore we have to use NAT overload (or PAT)

Double click on the Weaver router to open it

Router>enable Router#configure terminal

First you should change the router's name to Weaver

Router(config)#hostname Weaver

Create a NAT pool of global addresses to be allocated with their netmask. Weaver(config)#ip nat pool mypool 198.18.184.105 198.18.184.110 netmask 255.255.255.248

Create a standard access control list that permits the addresses that are to be translated.

Weaver(config)#access-list 1 permit 192.168.100.16 0.0.0.15

Establish dynamic source translation, specifying the access list that was defined in the prior step.

Weaver(config)#ip nat inside source list 1 pool mypool overload

This command translates all source addresses that pass access list 1, which means a source address from 192.168.100.17 to 192.168.100.30, into an address from the pool named mypool (the pool contains addresses from 198.18.184.105 to 198.18.184.110). Overload keyword allows to map multiple IP addresses to a single registered IP address (many-to-one) by using different ports.

The question said that appropriate interfaces have been configured for NAT inside and NAT outside statements.

This is how to configure the NAT inside and NAT outside, just for your understanding:

Weaver(config)#interface fa0/0 Weaver(config-if)#ip nat inside Weaver(config-if)#exit Weaver(config)#interface s0/0 Weaver(config-if)#ip nat outside Weaver(config-if)#end

Finally, we should save all your work with the following command:

Weaver#copy running-config startup-config

Check your configuration by going to "Host for testing" and type:

C :\>ping 192.0.2.114

The ping should work well and you will be replied from 192.0.2.114

Q9.  - (Topic 8)

Which MTU size can cause a baby giant error?

A. 1500

B. 9216

C. 1600

D. 1518

Answer: C

Explanation: http://www.cisco.com/c/en/us/support/docs/switches/catalyst-4000-series-switches/29805-175.html

Q10.  - (Topic 8)

How does NAT overloading provide one-to-many address transalation?

A. it uses a pool of addresses.

B. it converts IPv4 addresses to unused IPv6 addresses.

C. it assigns a unique TCP/UDP port to each session.

D. it uses virtual MAC address and virtual IP addresses.

Answer: C