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Sunday, May 20, 2007

CCNA Exam Topic: Implementation & Operations - 2

Continuation of Implementation & Operations CCNA actual exam topic questions.


Question 21:
A network administrator is configuring the routers in the graphic for OSPF. The OSPF process has been started and the networks have been configured for Area 0 as shown in the diagram. The network administrator has several options for configuring RouterB to ensure that it will be preferred as the designated router (DR) for the 172.16.1.0 /24 LAN segment. What configuration tasks could be used to establish this preference? (Choose three.)



A. Configure the priority value of the Fa0/0 interface of RouterB to a higher value than any other interface on the Ethernet network.
B. Change the router id of Router B by assigning the IP address 172.16.1.130/24 to the Fa0/0 interface of RouterB.
C. Configure a loopback interface on RouterB with an IP address higher than any IP address on the other routers.
D. Change the priority value of the Fa0/0 interface of RouterB to zero.
E. Change the priority values of the Fa0/0 interfaces of RouterA and RouterC to zero.
F. No further configuration is necessary.

Answer: ACE

Question 22:
Refer to the graphic. Two 2950 switches connect through ports Fa0/24 and a straight-through cable. Based on the output of the show cdp neighbor command from both switches and the information given, what can be concluded?
A. Port Fa0/24 on each switch must be configured in VLAN 1 in order for the switches to see neighbor information.
B. Port Fa0/24 on each switch must be configured as a trunk port in order for neighbor information to be received.
C. The switches are not cabled properly.
D. An IP address needs to be assigned to both switches.
E. VTP is incorrectly configured on switch A.

Answer: C

Question 23:
Refer to the topology and router configuration shown in the graphic. A host on the LAN is accessing an FTP server across the Internet. Which of the following addresses could appear as a source address for the packets forwarded by the router to the destination server?
A. 10.10.0.1
B. 10.10.0.2
C. 199.99.9.33
D. 199.99.9.57
E. 200.2.2.17
F. 200.2.2.18

Answer: D

Question 24:
Refer to the graphic. A company wants to use NAT in the network shown. Which commands will apply the NAT configuration to the proper interfaces? (Choose two.)
A. R1(config)# interface serial0/1
R1(config-if)# ip nat inside
B. R1(config)# interface serial0/1
R1(config-if)# ip nat outside
C. R1(config)# interface fastethernet0/0
R1(config-if)# ip nat inside
D. R1(config)# interface fastethernet0/0
R1(config-if)# ip nat outside
E. R1(config)# interface serial0/1
R1(config-if)# ip nat outside source pool 200.2.2.18 255.255.255.252
F. R1(config)# interface fastethernet0/0
R1(config-if)# ip nat inside source 10.10.0.0 255.255.255.0

Answer: BC

Question 25:
Refer to the graphic. Which of the following commands would create the output shown at the bottom of the graphic?
A. Router# show ip eigrp topology
B. Router# show ip route
C. Router# show ip eigrp neighbors
D. Router# show ip ospf route
E. Router# show ip ospf database

Answer: A

Question 26:
Refer to the exhibit. Which ports could safely be configured with PortFast? (Choose two.)

A. Switch1 - port Fa1/2
B. Switch2 - port Fa1/2
C. Switch1 - port Fa1/3
D. Switch2 - port Fa1/3
E. Switch1 - port Fa1/1
F. Switch2 - port Fa1/1

Answer: CD

Question 27:
Refer to the exhibit. Communication with the Internet is vital to all networks belonging to the corporation. On which of the four routers shown in the graphic should a default route be configured, assuming that a routing protocol is being used to distribute the default route? A. A
B. B
C. C
D. ISP

Answer: A

Question 28:
Refer to the graphic. It has been decided that Workstation 1 should be denied access to Server1. Which of the following commands are required to prevent only Workstation 1 from accessing Server1 while allowing all other traffic to flow normally? (Choose two.)

A. RouterA(config)# interface fa0/0
RouterA(config-if)# ip access-group 101 out
B. RouterA(config)# interface fa0/0
RouterA(config-if)# ip access-group 101 in
C. RouterA(config)# access-list 101 deny ip host 172.16.161.150 host 172.16.162.163
RouterA(config)# access-list 101 permit ip any any
D. RouterA(config)# access-list 101 deny ip 172.16.161.150 0.0.0.255 172.16.162.163 0.0.0.0
RouterA(config)# access-list 101 permit ip any any

Answer: BC


Question 29:
Refer to the topology and command output within the exhibit. When hosts on the 172.16.5.0 network attempt to ping the remote server at 192.168.145.27, the message "Reply from 192.168.145.27:TTL expired in transit" is returned. What is the cause of this problem?

A. No static route is configured on the SOHO router to the 192.168.145.0 network.
B. No static route is configured on the ISP router to the 192.168.145.0 network.
C. A routing protocol must be configured to send packets between SOHO and ISP.
D. A routing loop has occurred.

Answer: D

Question 30:
Refer to graphic and examine the output from the London switch . What VTP functions will this switch perform?
A. create, change, and delete VLANs for the VTP domain
B. learn and save VTP configuration information in the running configuration only
C. forward VTP configuration information
D. backup the VTP database for the closest VTP server
E. prevent VTP information from reaching workgroup switches

Answer: C

Question 31:
Refer to the exhibit. Based on the exhibited routing table, how will packets from a host within the 192.168.10.192/26 LAN be forwarded to 192.168.10.1?
A. The router will forward packets from R3 to R2 to R1.
B. The router will forward packets from R3 to R1 to R2.
C. The router will forward packets from R3 to R2 to R1 AND from R3 to R1.
D. The router will forward packets from R3 to R1.

Answer: C

Question 32:
A network administrator needs to verify that switch interface 0/5 has been assigned to the Sales VLAN. Which command will accomplish this task?

A. show vlan
B. show mac-address-table
C. show vtp status
D. show spanning-tree root
E. show ip interface brief

Answer: A

Question 33:
Refer to the exhibit. Host A needs to send data to Host B. Which Layer 2 and Layer 3 destination addresses will be used to send the data from Host A to Host B?
A. 192.168.60.5 and 0011.43da.2c98
B. 192.168.60.5 and 0007.0e56.ab2e
C. 192.168.24.1 and 0007.0e56.ab2e
D. 192.168.24.2 and 0007.0e84.acef

Answer: B

Question 34:
Refer to the exhibit. What is the correct addressing for a frame and packet received by Host B from Host A?

A. Destination MAC: 0011.43da.2c98
Source MAC: 0070.0e8f.088a
Destination IP: 192.168.60.5
Source IP: 192.168.24.5
B. Destination MAC: 0011.43da.2c98
Source MAC: 00b0.d0ef.5f6a
Destination IP: 192.168.60.5
Source IP: 192.168.24.5
C. Destination MAC: 0011.43da.2c98
Source MAC: 0070.0e8f.088a
Destination IP: 192.168.60.5
Source IP: 192.168.60.1
D. Destination MAC: 0011.43da.2c98
Source MAC: 0070.0e97.af4e
Destination IP: 192.168.60.5
Source IP: 192.168.60.2

Answer: A

Question 35:

Refer to the exhibit. Switch-1 needs to send data to a host with a MAC address of 00b0.d056.efa4. What will Switch-1 do with this data?

A. Switch-1 will drop the data because it does not have an entry for that MAC address.
B. Switch-1 will flood the data out all of its ports except the port from which the data originated.
C. Switch-1 will send an ARP request out all its ports except the port from which the data originated.
D. Switch-1 will forward the data to its default gateway.

Answer: B

Question 36:
Why has the network shown in the exhibit failed to converge?
A. The no auto-summary command needs to be applied to the routers.
B. The network numbers have not been properly configured on the routers.
C. The subnet masks for the network numbers have not been properly configured.
D. The autonomous system number has not been properly configured.
E. The bandwidth values have not been properly configured on the serial interfaces.

Answer: A

Question 37:
Refer to the exhibit. A network associate has configured OSPF with the command:
City(config-router)#network 192.168.12.64 0.0.0.63 area 0
After completing the configuration, the associate discovers that not all the interfaces are participating in OSPF. Which three of the interfaces shown in the exhibit will participate in OSPF according to this configuration statement? (Choose three.)
A. FastEthernet0 /0
B. FastEthernet0 /1
C. Serial0/0
D. Serial0/1.102
E. Serial0/1.103
F. Serial0/1.104

Answer: BCD

Question 38:
Refer to the exhibit. What can be determined about the interfaces of the Main_Campus router from the output shown?
A. The LAN interfaces are configured on different subnets.
B. Interface FastEthernet 0/0 is configured as a trunk.
C. The Layer 2 protocol of interface Serial 0/1 is NOT operational.
D. The router is a modular router with five FastEthernet interfaces.
E. Interface FastEthernet 0/0 is administratively deactivated.

Answer: B

Question 39:
Refer to the output of the two show commands in the exhibit. If an administrator tries to ping host 10.1.8.5 from host 10.1.6.100, how will the ICMP packets be processed by Router A?
A. The packets will be discarded.
B. The packets will be routed out the S0/0 interface.
C. The packets will be routed out the S0/1 interface.
D. The packets will be routed out the Fa0/0 interface.

Answer: C

Question 40:
Refer to the exhibit. Assuming that the entire network topology is shown, what is the operational status of the interfaces of R2 as indicated by the command output shown?
A. One interface has a problem.
B. Two interfaces have problems.
C. The interfaces are functioning correctly.
D. The operational status of the interfaces cannot be determined from the output shown.

Answer: C

Question 41:
Refer to the exhibit. A network technician is asked to design a small network with redundancy. The exhibit represents this design, with all hosts configured in the same VLAN. What conclusions can be made about this design?
A. This design will function as intended.
B. Spanning-tree will need to be used.
C. The router will not accept the addressing scheme.
D. The connection between switches should be a trunk.
E. The router interfaces must be encapsulated with the 802.1Q protocol.

Answer: C

Question 42:
A company is experiencing network delays. The network administrator discovers that a worker in a location far from the MDF has connected an old 10BASE-T switch with redundant links to the existing network. How could this action be responsible for the impaired network performance?

A. Connecting a host to the old switch has created a broadcast storm.
B. The 10BASE-T switch forced the entire network to be reduced to 10 Mbps operation.
C. The old switch does not support VLANs, which has disabled the VLAN configuration of the entire the network.
D. The old switch does not support full-duplex operation, effectively forcing half-duplex operation throughout the network.
E. Spanning Tree Protocol has elected the old switch as the root bridge, creating inefficient data paths through the switched network.

Answer: E

Question 43:
Refer to the exhibit. What does STATUS=ACTIVE refer to in the output of the show frame-relay pvc command?
A. The PVC is experiencing congestion.
B. The Frame Relay switch is correctly programmed with the DLCI and is operational.
C. The router is actively broadcasting to establish a link to the Frame Relay switch.
D. The router is connected to the local Frame Relay switch, but not to the far end device.

Answer: B

Question 44:
Refer to the exhibit. The Lakeside Company has the internetwork in the exhibit. The administrator would like to reduce the size of the routing table on the Central router. Which partial routing table entry in the Central router represents a route summary that represents the LANs in Phoenix but no additional subnets?
A. 10.0.0.0/22 is subnetted, 1 subnets
D10.0.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1
B. 10.0.0.0/28 is subnetted, 1 subnets
D10.2.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1
C. 10.0.0.0/30 is subnetted, 1 subnets
D10.2.2.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1
D. 10.0.0.0/22 is subnetted, 1 subnets
D10.4.0.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1
E. 10.0.0.0/28 is subnetted, 1 subnets
D10.4.4.0 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1
F. 10.0.0.0/30 is subnetted, 1 subnets
D 10.4.4.4 [90/20514560] via 10.2.0.2, 6w0d, Serial0/1

Answer: D

Question 45:
Refer to the exhibit. Which two statements describe the OSPF relationships between the routers? (Choose two.) A. R3 is fully adjacent with R2 and is the DR for the 192.168.2.4 network.
B. R3 is fully adjacent with R1 and is the DR for the 10.1.1.0 network.
C. R3 is fully adjacent with R2 and is the BDR for the 10.1.1.0 network.
D. R2 is fully adjacent with R1 and is the BDR for the 10.1.1.0 network.
E. R3 is fully adjacent with routers R1 and R2
F. R2 is the DR for networks 192.168.1.0 and 172.16.2.0.

Answer: BE

Question 46:
Based on the topology table that is shown in the exhibit and assuming that variance is not configured for EIGRP, which route or routes should appear in the routing table?


A. D 192.168.8.20 (2707456/2195456), Serial0/1
B. D 192.168.2.0/24 [90/2707456] via 192.168.8.22, 00:27:50, Serial0/0
[90/3815424] via 192.168.8.18, 00:27:50, Serial0/2
C. D 192.168.2.0/24 [90/3815424] via 192.168.8.18, 00:27:50, Serial0/2
D. D 192.168.8.24/30 [90/2681856] via 192.168.8.22, 00:27:50, Serial0/0

Answer: D

Question 47:
Refer to the exhibit. The network has been configured with STP disabled. HostA sends an ARP request for the IP address of a site on the Internet. What will happen to this ARP request? (Choose two.)
A. Because the ARP request is a broadcast, SW-A will not forward the request.
B. SW-A will convert the broadcast to a unicast and forward it to SW-D.
C. The switches will propagate the broadcast, creating a broadcast storm.
D. From a port on SW-A, HostA will receive an ARP reply containing the MAC address.
E. From the Ethernet interface of RouterX, HostA will receive an ARP reply that contains the MAC address.
F. The switches will propagate the broadcast until the TTL of the frame reduces to 0. Then the frame will be discarded.

Answer: CE

Question 48:
Refer to the exhibit. Spanning Tree Protocol has created a loop-free logical topology in the network that is pictured. How many ports have been placed in the blocking mode?
A. none
B. one
C. two
D. three
E. four

Answer: C

I am currently working on this page, Meanwhile check the archive section

50 comments:

Johnson said...

On Q44, P4sure is given the answer is F.

Can you provide the explanation?

a3tips said...

Hi Johnson,
Q44 tells Which partial routing table entry in the Central router represents a route summary that represents the LANs in Phoenix but no additional subnets?

Phoenix four lans are 10.4.3.0, 10.4.2.0 , 10.4.1.0 and 10.4.0.0
to make a summary route for these 4 LANS .
the first two octets are similar to all 4 networks.
3rd octet is which we are concerend of
10.4.3.0 = ( 3 of 3rd octet can be represented in bits 0000 0011)
10.4.2.0 = ( 2 = 0000 0010)
10.4.1.0 = ( 1 = 0000 0001)
10.4.0.0 = (0 = 0000 0000)
now if we take the similar bits in 3rd octets first 6 bits match for all four LANS.

so the new summary route subnet is
8 bits(1st octet) + 8bits (2nd octet) + 6bits (3rd octet) = 22bits

10.4.0.0 /22 is the summary route.

Hope this helps,
Cheers

Anonymous said...

on question no3 in p4s ver2.83 it gives answer c . is it correct explain plz thank u

Anonymous said...

Can any explain the answer to qtn 31 please I will aprre ite thanks in advance.

a3tips said...

Q3 on p4s ver2.83 it gives answer c.
It is correct answer.
Explanation:
to calculate summary route for following networks
172.1.4.0 /25
172.1.4.128 /25
172.1.5.0 /24
172.1.6.0 /24
172.1.7.0 /24
first two octets are same for all 5 networks.

3rd octet is which we are concerned of
172.1.4.0 = (4 of 3rd octet can be represented in bits 0000 0100)
172.1.4.128= (4 = 0000 0100)
172.1.5.0 = ( 5 = 0000 0101)
172.1.6.0 = ( 6 = 0000 0110)
172.1.7.0 = ( 7 = 0000 0111)
now if we take similar bits in 3rd octet first 6bits match for all 5 LANs

summary route is
8bits(1st octet) + 8bits (2nd octet)+ 6 bits (3rd octet)
= 22 bits

172.1.4.0 /22
This is option C in P4s
Hope this helps
cheers

Colm said...

Hi johnson, On Q40 i think on R2 S0/1 is on the same network as FA0/0 so I dont think they will function properly. Am I correct.

a3tips said...

Hi Colm,

both interfaces are on different networks R2 fa 0/0 has /26 network mask
and R1 s0/0 has /30 network mask.

and the question is based on the output.
According to the output we find that all interfaces operation status are UP. except the s 0/0 on R2 which is administratively down.

So all interfaces are working properly is the correct option

Hope this helps
Cheers
A3

Anonymous said...

My attempt at Question 31:

Because both routes listed for 192.168.10.0/30 have the same admin/cost (90/2681856), the router sends the packets down both.

-zomg

a3tips said...

Hi Zomg,

Yes you are correct for q31. since 192.168.10.0 ntw has two successor routes installed in routing table.

The answer is C
Hope this helps
Cheers

Monte said...

Hi

Q38 isn't answer A correct too?

Q48 can u explain how you got answer C?

thanks

Monte

Anonymous said...

hi,
I don't understand question #23; can you explain.

Anonymous said...

please explain Q44. Why /22?

a3tips said...

Question 23 asks about which source address the ftp destination server recieves when a host on lan access it.

LAN Host IP address is from 10.10.0.0 /24

The router is configured with NAT Pool name test (199.99.9.40 - 199.99.9.62)

Command on router:
ip nat inside source list 1 pool test
translates the source list 1 ( access-list 1 match address 10.10.0.0 /24)
IP address into Pool name Test address (199.99.9.40-199.99.9.62)
This translation occurs when host on LAN try to get into internet
So the source address that is viewed by ftp server is 199.99.9.57 (Which is part of the pool name test address range)

Hope this helps
Cheers

a3tips said...

Hi Monte,

Q38:
Option A tells about The LAN interfaces are configured on different subnets.

If you carefully observe the exhibit you find subinterfaces created on Fa 0/0.

option A tells about interfaces and more over we only have one interface on router how can we configure different subnets on single fa 0/0.

Hope this helps
Cheers

a3tips said...

Hi Monte:

Q48:
To create a loop free topology for the given exhibit we need to block on port thats linking btw S1 and S3

Even after this their is a chance for Loops. That is the reason we need to block one more port.

Therefore the answer is 2 ports must be in blocking state for STP to create a loop-free logical topology in the network.

Hope this helps
Cheers

a3tips said...

HI Q44 was already explained in comments section anyhow i am posting it again.

Q44 tells Which partial routing table entry in the Central router represents a route summary that represents the LANs in Phoenix but no additional subnets?

Phoenix four lans are 10.4.3.0, 10.4.2.0 , 10.4.1.0 and 10.4.0.0
to make a summary route for these 4 LANS .
the first two octets are similar to all 4 networks.
3rd octet is which we are concerend of
10.4.3.0 = ( 3 of 3rd octet can be represented in bits 0000 0011)
10.4.2.0 = ( 2 = 0000 0010)
10.4.1.0 = ( 1 = 0000 0001)
10.4.0.0 = (0 = 0000 0000)
now if we take the similar bits in 3rd octets first 6 bits match for all four LANS.

so the new summary route subnet is
8 bits(1st octet) + 8bits (2nd octet) + 6bits (3rd octet) = 22bits

10.4.0.0 /22 is the summary route.

Hope this helps,
Cheers

Anonymous said...

Hi a3tips,

I'm having a little trouble understanding questions #28, #39, #45, and #46. Could you explain how you derived at the answers to these questions? I want to understand the theory.

a3tips said...

Hi,
Q28.
step 1:
Workstation1( 172.16.161.150) should be denied access to server 1 (172.16.162.163)
RouterA(config)# access-list 101 deny ip host 172.16.161.150 host 172.16.162.163

step2:
to allow all other traffic to flow normally permit any any
RouterA(config)# access-list 101 permit ip any any


Step 3:
Since extended ACLs needs to be placed near to source address

RouterA(config)# interface fa0/0

Filter all incoming packets on router fa 0/0

RouterA(config-if)# ip access-group 101 in

Answers :B (step3) C (step 1 & 2)
Hope this helps
Cheers

a3tips said...

Q39 Explanation:

The two show commands provide us that
RIP is configured and advertising 10.0.0.0 network

The show ip route command provides that
it has learned 10.1.3.0 network via RIP
and 10.1.2.0 , 10.1.5.0 & 10.1.6.0 ntw are directly
connected.

Also via Rip it has learned default route via serial 0/1

Since host 10.1.6.100 is on fa 0/0 and directly connected
when it tries to ping 10.1.8.5 network Since their is no route to 10.1.8.0 ntw in routing
table the router forwards out the packets to the default route via serial 0/1

Answer: A


Hope this helps
Cheers

salmaan kamil said...

can u please explain me question no 46 ?

salmaan

a3tips said...

Hi salman,

Question 46

Explanation:
The command show ip eigrp topology displays eigrp topology table which consist of all known routes by eigrp.

The path with the lowest metric(Lowest Feasible distance FD ) is called the successor path. This successor routes are installed into the routing table.
Multiple successor routes for particular network can exist in routing table.

Based on above statement after verifying the output of show ip eigrp topology

option D route will be installed into routing table.

D (Eigrp route) 192.168.8.24/30 [90 (AD of EIGRP) /2681856 (FD of successor)] via 192.168.8.22, 00:27:50, Serial0/0

Note other successor routes for other three ntws will also be installed into routing table but they are not provided correctly in the q46 options.

Hope this helps
Cheers

salmaan kamil said...

dude i cleared ccna with 961 marks
thanks for ur help

Anonymous said...

Explain question 41 Please

a3tips said...

Hi

Q41

Routers both fastethernet are configured with same ntw (192.168.1.0 /24) and subnet mask

Example consider fa 0/0 Ip address : 192.168.1.1 255.255.255.0

If you try to configure the ip address 192.168.1.2 255.255.255.0 on fastethernet 0/1 as mentioned in the exhibit you will get an error message

% 192.168.1.0 overlaps with FastEthernet 0/0

Hope this helps

Cheers

Anonymous said...

Great CCNA preparation site! Thanks for all your work. Can you please explain Q45?

a3tips said...

Q45:

the command show ip ospf neighbor on R3 output provides the following information

Neighbor ID is the router ID used for Ospf process.

Firs line in exhibit neighbor ID 192.168.2.5 is the router ID of R2

Since the link between R3 and R2 is serial point-to-point link
their will be no DR /BDR elections and also the state in exhibit confirms this by showing Full/-

Full here means routers formed a fully adjacent state (R3 and R2).

Second Line provides:
Neighbor ID 172.16.2.5 which is the router ID of R1
The link between R3 and R1 is shared medium so DR/BDR election takes place for network 10.1.1.0.

The state FULL/BDR provides that address 10.1.1.1 (R1) is the BDR for network 10.1.1.0 . Which makes R3 (10.1.1.2 higher ip address) to be DR for this network.

Full in exhibit again confirms that R3 and R1 are fully adjacent.

From the above explanation we can conclude option B and E are correct
B: R3 is fully adjacent with R1 and is the DR for the 10.1.1.0 network.

E:R3 is fully adjacent with routers R1 and R2

Hope this helps

Cheers!!!!

Anonymous said...

Great blog. In q28 how come the answers are not A & C.?

a3tips said...

Hi
Q28 is already explained in the comment section here.


Cheers!!

Anonymous said...

Hi... best regards.
In the question 30. that answer C.

Could you explain why it is that response?
Because I understand that transparent mode no sends information VTP.

a3tips said...

Hi
Q30:

transparent switches do forward VTP advertisements that they receive out their trunk ports in VTP Version 2.

http://www.cisco.com/en/US/tech/tk389/tk689/technologies_tech_note09186a0080094c52.shtml#vtp_modes

Hope this helps

Cheers!!!

Anonymous said...

please can u explain me what is the idea behind setting a loopback address on a router...appreciated.

a3tips said...

please can u explain me what is the idea behind setting a loopback address on a router...appreciated.


Which question number you are asking about

Cheers

Anonymous said...

Hi,

In Q21 you selected A as 1 of the 3 answers, however isnt lower priority preferred in the election process?

A. Configure the priority value of the Fa0/0 interface of RouterB to a higher value than any other interface on the Ethernet network

a3tips said...

Q21:

DR/BDR election is by virtue of a higher priority configured on the router.

Priority set to 0 does not allow router to particpate in DR/BDR election.

Priority set to 255 is the highest a router can have and high possibility of becoming DR.

Hope this helps
Cheers

John said...

HI a3tips,

Would you mind to explain me Q22 please. I think the correct answer would be B.

Anonymous said...

Hi a3tips,

Would you mind to explain Q22? i think the correct would be B.

a3tips said...

Hi John,
q22 provides Two 2950 switches connect through ports Fa0/24 and a straight-through cable.

Explanation:
To connect two switches we need a crossover cable..

by using straight-through cable the link btw both switches will not be up.

Hope this helps

Cheers!!!

Anonymous said...

Q47 answer should be CF and not CE.

Kindly confirm! :-)

Will do CCNA 640-802 this month!

a3tips said...

Hi
Q47 options CE are correct.

Since first Host sents ARP request to switch which does not have the mac-addresss it will broadcast out its all interface other than from where it received the frame.
This created broadcast storm in switched ntw.

Also sw-D has a port toward Router which in turn provides the ARP reply and finally reaches the Host.

This way the arp request is completed.
More over their will be no TTL reduction done when frames move from one switch to other. It (TTL option)is used by Router to drop or discard PACKET once it travels over diff hops.

Hope this helps

cheers!!!

Anonymous said...

hi,
can u please explain q 48 , how u derived 3. thanks in advance.

shirish.

a3tips said...

Hi,

Q48.

Explanation:

Refer exhibit for Q48.

By verfiying physical topology they are chance of frames looping
between S2-S1-S3 , S1-S4-S3 and S2-S1-s4-s3.

STP sets ports into blocking mode for redundant ports.
To form loop free logical topology we need to BLOCK
1: On S3 Port going towards S2
2: on S4 Port going towards S3
By blocking above two ports we achieve a loop free Logical topology with full connectivity.

Hope this helps

Cheers

Primus Pilus said...

In q22. why is answer B incorrect ? Thanks

B. Change the router id of Router B by assigning the IP address 172.16.1.130/24 to the Fa0/0 interface of RouterB.

a3tips said...

Hi,
Is it Q21 you are talking about...

If you use Option B assigning the IP address 172.16.1.130/24 to the Fa0/0 interface of RouterB. Will set the Router ID of Router B.

When you configure a loopback interface (Option C) on router B it will take over as the router ID of Router B.

So the purpose of configuring the Ip address 172.16.1.130 does not have effect it to be a DR.

So if u select Option C as one of your answer .. option B will not be a valid answer.

Hope this helps

cheers!!

aando74 said...

Great Blog !!!
Could you explain question 29?

a3tips said...

Hi,

Q29

Explanation;

When hosts on the 172.16.5.0 network attempt to ping the remote server at 192.168.145.27

As per exhibit.. this ping packet reaches SOHO router.. No route is present on SOHO routing table for 192.168.145.27 since it has a default route on SOHO this will be used.. However once it reaches ISP router similarly ISP router does not have a route to 192.168.145.27 and a default route is pointed towards SOHO.. this way the packet gets looped between SOHO and ISP router still the 16 hop max counts reached and TTL expires..

Therefore option D is correct..
A routing Loop occured.

Hope this helps

Cheers!!!

berad said...

Q45

A3Tips says in explaining q45:

The state FULL/BDR provides that address 10.1.1.1 (R1) is the BDR for network 10.1.1.0 . Which makes R3 (10.1.1.2 higher ip address) to be DR for this network.

berad says:

Your explanation is right on except for one small detail.

I think the router ids are R1 172.16.2.5 and R3 192.168.2.6 which still agrees on R3 is the DR and R1 is the BDR (assuming that the priority is at default of 1 and the router id has not been manually set on R3 - which you can't tell from this output)

a tough problem because you have to remember that point to point links don't elect DR and BDR.

When the DR/BDR election is held: Priority is the first criterion with the higher priority winning, then router id which is determined manually with the router-id command or if not configured then the highest loopback ip and if no loopback interface then the highest ip address of an active port becomes the router id.

Thanks for the help on this tough question. I hope my thoughts are correct and may help someone.

Mike Tomato said...

Hi all,

with regards to question 43, I took the 640-801 test yesterday and the only difference was that instead of:

"Refer to the exhibit. What does STATUS=ACTIVE refer to in the output of the show frame-relay pvc command?"

my question did not have an exhibit, and the status was INACTIVE.

My 2 cents.

Cheers,
Rafael

miro said...

Hi,
i want ask about question number 33.
Why in the correct answer, a destination MAC address is a address of router1, but not MAC address of switch1 ?

please explaian

a3tips said...

Hi Miro,
Q33 Explanaton:

Remember Host A is in different subnet network then Host B for this two to communicate we need Router help.

So when host A tries to communicate it needs to use its Router MAC (layer2 address) and HostB (Layer3 address) in destination fields.

Router will forward this packets to Host B thats reason we use router MAC address ; Since host A directly can not communicate to Host B it uses Router help to communicate .

Hope this helps
Cheers

hari said...

Hi johnson, On Q40 i think on R2 S0/1 is on the same network as FA0/0 In r2 s0/1 --172.16.109.5/30
F0/0---172.16.109.62/26 both ip add are same subnet so it will overlap
And finally it will not work correctly I think Ans-C is wrong
so I dont think they will function properly. Am I correct.