InterVLAN Routing
Here you will find answers to InterVLAN Routing questions
Question 1:
Study the exhibit carefully. Both host stations are part of the same subnet but are in different VLANs. On the basis of the information presented in the exhibit, which statement is true about an attempt to ping from host to host?

A – Layer 3 device is needed for the ping command to be successful.
B – A trunk port will need to be configured on the link between SA and SB for the ping command to be successful.
C – The two different hosts will need to be in the same VLAN in order for the ping command to be successful.
D – The ping command will be successful without any further configuration changes.
Answer: D
Explanation:
For two hosts in different VLANs, we must use a layer 3 device to transport packages between them. However, in this case both switches are set in “access” mode therefore the VLAN information sent between them will be set as untagged. Moreover, they are in the same subnet so they can ping each other without a layer 3 device.
Question 2:
Based on the following exhibit, which problem is preventing users on VLAN 100 from pinging addresses on VLAN 200?

A – Native VLAN mismatch.
B – Subinterfaces should be created on Fa0/7 and Fa0/8 on DLS1.
C – Trunking needs to be enabled.
D – The ip routing command is missing on DLS1.
Answer: D
Explanation:
To allow communication between two VLANs, we need to enables Layer 3 routing on the switch with the “ip routing” command. Some flatforms are enabled by default but some are not.
Question 3:
Based on the network diagram and routing table output in the exhibit, which one of these statements is true?

A – InterVLAN routing has been configured properly, and the workstations have connectivity to each other.
B – InterVLAN routing will not occur since no routing protocol has been configured.
C – Although interVLAN routing is not enabled, both workstations will have connectivity to each other.
D – Although interVLAN routing is enabled, the workstations will not have connectivity to each other.
E – None of the above.
Answer: A
Explanation:
In the output we can see both VLAN10 and VLAN20 are shown up (as networks 10.1.1.0 and 10.2.2.0) so the routing has been configured properly. Notice that the “C” letter indicates that these networks are directly connected with the router.
Question 4:
Study the following exhibit carefully, what is the reason that users from VLAN 100 can’t ping users on VLAN 200?

A – IP routing needs to be enabled on the switch
B – Trunking needs to be enabled on Fa0/1
C – VLAN 1 needs the no shutdown command
D – The native VLAN is wrong
Answer: B
Explanation:
The Fa0/1 interface on the switch is not configured with trunking mode. It needs to be configured as shown below:
SA(config)#interface Fa0/1
SA(config-if)#switchport mode trunk
SA(config-if)#switchport trunk encapsulation dot1q
Question 5:
Assume that a host sends a packet to a destination IP address and that the CEF-based switch does not yet have a valid MAC address for the destination. How is the ARP entry (MAC address) of the next-hop destination in the FIB get?
A – The sending host must send an ARP request for it
B – All packets to the destination are dropped
C – The Layer 3 forwarding engine (CEF hardware) must send an ARP request for it
D – CEF must wait until the Layer 3 engine sends an ARP request for it
Answer: D
Explanation:
If a valid MAC address for the destination is not found, the Layer 3 forwarding engine can’t forward the packet in hardware due to the missing Layer 2 next-hop address. Therefore the packet is sent to the Layer 3 Engine so that it can generate an ARP request (this is called the “CEF glean” state)

Question 6:
CEF is a complete new routing switch technology . Which two table types are CEF components?(Choose two)
A – adjacency tables
B – caching tables
C – neighbor tables
D – forwarding information base
Answer: A D
If I could make a request. Make the answer hidden until clicked. You could use some simple HTML to hide the answer until you click on it. Other wise great stuff taking test tomorrow hope it helps.
I would have to agree with Maokin. Actually, an easier thing for the admin would be to have a a line that says “Answer”, and then the actual answer a few lines below that, so when scrolling you get some warning..
hi do you like car rims?
good idea!!!
Is there anymore questions?
Is it possible to download as PDF?
Why don’t you stop complaining and be grateful this material is available?
Re Q1, so what is the function of “switchport access vlan x” command? Does it mean that the switch will apply a VLAN tag x ONLY when the traffic is traversing a trunk? If not, then it remains untagged. Please confirm. Many thanks.
hallo Mb_rahman
The comand ” switchport access vlan X ” will associate the port to valn x
The answer to mb_rahman’s question (January 14th, 2011) is YES; The switch will apply a VLAN tag x ONLY when the traffic is traversing a trunk? If not, then it remains untagged.
@Root, It is not a complain but a suggestion to improve the site. Nobody said that they are not grateful for the content. Cheers.
I think that keeping this as it is, is best. There are test engines out there that I spent money on to get that “real test” feel, but they rely on flash and other things that aren’t as friendly to a work computer. Thank you to the author for keeping this site as is and up to date with the best info.
I am giving my exam tomorrow…dont know whats gonna happen
@anxious
best of luck
please share ur experience as well
Not too sure about Q1
if G0/1 is part of one vlan and the other G0/1 is part of another vlan how could it work at first ?
please clarify, i might be wrong
Easier way to do it is to put the answers in white font colour. Then to see the answer you have to highlight the text. I think that works well
@ Anonymous: A good idea but that will still require html requiring to change font color.
WHY DONT WE JUST SCROLL DOWN SLOWLY AND HIDE THE ANSWER? IT WORKS GREAT FOR ME.
Q1. The answer should be A. For devices in different vlan, a router is required to communicate. I verified the same in packet tracer.
Q1)
The two routers are in the same subnet, so they need to be in the same VLAN to communicate, as we apply a subnet per VLAN. VLANs act like a broadcast domain. I beleive the answer is A.
Regards,
Sarah
Q1 answer is D. I have this scenario working in a production network for over 2 years without any issues.
@Sarah
Hello,
I understand that in a switchport access vlan x configuration, when the frame comes in the bridge is identified as of an specific vlan, x in this case.
So when the frame comes in SA from PC1, SA identifies the frame as VLAN2, and since G0/1 is in VLAN2 as well, the ARP broadcast requesting who is the destination ip, is flooded under that port and reaches SB.
When it enters SB, it will be identified now as VLAN5 and will reach PC2 in VLAN5 as well.
When PC2 replies, the same process will occur: PC2 sends a frame that gets identified in SB with VLAN5, and SB will send the response through the GIG link back to S1.
When it reaches S1 it will be now identified again with VLAN2, therefore reaching PC1 in VLAN2 as well.
Thanks to CISCO for creating head splitting questions
I would sort of compare this setup with a L2 NAT, where the identification of the local VLAN (2) gets translated at the remote destination VLAN (5) and back again.
I would answer D. Yet I’ll lab it up tomorrow and post.
@Chrisp
Is there some foundation behind this setup in production ?
Would you be so kind to elaborate as to the why of this design ?
I have some screenshots of a Test Inside obtained about 1 month ago, if someone has similar data perhaps from a late P4S we could swap ?
tiempo21@hotmail.com
I am planning to take a second try at the 642-813 this coming Friday 24th, so all information is appreciated.
Thanks for the site and input to all !
Q1 correct answer is A… i know a production enviroment which has that scenario.
@erick in Q1 the answer is D – The ping command will be successful without any further configuration changes.
But u can split the broadcast in vlans, it’s act like just 1 VLAN, check it out in lab with real switches, gns3 or packet tracer, you’ll see it. =)
You’re the graetset! JMHO
I got Question 4 in my exam today!
Hi.
1. This reply is for question number 1
2. I am just adding some information that I believe may be useful.
3. Treat the VLAN’s as separate switches. ( That is what they are meant to work as, if they are on a single switch)
4. So we have a separate switch numbered ’2′ and a separate switch numbered ’5′ on either side.
5. We have connected them using a cross cable.
6. As long as the PC’s connected to the ports are in same ip network they will ping.
7. Rest of the information is already explained with respect to tagged frames in case of trunk ports.
8. This was a very informative question.
Take care.
Hi.
1. More information based on reply by
“erick on June 23rd, 2011
Q1 correct answer is A… i know a production environment which has that scenario.”
2. If Switch A and Switch B were connected using a trunk port, then a Layer 3 device would be required.
.
3. For all other situations, previous answer stands
4. This was an interesting question as it clears at least three fundamental concepts about:
a. VLANs
b. Trunks
c. VLAN tagging.
5. Just a humble suggestion, do not argue about the answer. It is right. Just learn – it will really help you on a long run.
Take care.
Can anyone please mail me link or file of latest dumps of 642-813 .i have version6.8 but on pss4sure.com it has been changed at 26th august.
please help me
Email id is baig_0236@yahoo.com
Hi guys
I`ll make my exam next week, i want to know how much(generally) of question about wireless and voice appers on the exam ?
Already talked to some people and I was told not appear more than two questions from each topic, this is true?
Thank you
I realized the scenario on the packet tracer and the anwer of the question 1 , yes its D , please check it out.
Question 3:
C – Although interVLAN routing is not enabled, both workstations will have connectivity to each other.
Intervlan routing is on the switch. Routing is on the router. So we have no intervlan routing enabled but we have routing in the router and the host will see one with eachother.
Maybe they say that intervlan routing is made by the router.
I hate this kind of question when the answer is discutable.
Hi guys
Question 4 should be more explicit about the interface connected to the router. We assume its fa0/1.
Is it like this in the exam? Getting ready. It’ll be in a week
i do not agree on the answer for the first question because since the two pcs belong two different VLANs even thought they are on the same subnet ,b/c vlans separates broadcast domain so we need a layer 3 device to be configured as well i have tried it on my packet tracer.what do u think friends?
Hi Abb,
Note that vlan tags are removed from frames when sending OUT of an access port. VLAN tags are not passed between switches unless through a trunk port.
@Chrisp – that sounds like a great “production” network……idiot
Hey oi… have you noticed that you are the only one with derogatory comments here… what does that make you? Calm down and enjoy the information that’s provided.
Hi,
Can someone guide pattern of switch exam.
Just simulated Q1 scenario
D – The ping command will be successful without any further configuration changes-IS CORRECT
Anyhow if we do the same scenario on a single switch
2 PCs in one subnet
associate 1 port with VLAN 2 and other one with VLAN 5 ping will be UNSUCCESSFUL
All friends,
Can anyone please mail me link or file of latest dumps of 642-813 ccnp switch
Please help me.
Email id : vijendra.s@consularis.co.in
Thanks,
Vijendra Sawant.
thank you nonentity …. after next week i see u in tshoot site…. are u going to do a vce for it? hhh
)
ccnp soooooon
@Vjendra
use this link
http://www.ziddu.com/download/17355977/CiscoActualTests642813v76bynonentity346QRev4.zip.html
the most current Switch exam to make you pass 1000/1000
@Quest4Knowledge, that is not the most current switch exam dump.
Hey guys , am about to write 642-813, can any one help me with the latest dump.
It has 499 questions.
Will rlly appreciate it.
All friends,
Can anyone please mail me link or file of latest dumps of 642-813 ccnp switch
Please help me.
Email id : Venkatraj030@gmail.com
Thanks,
Venkatachalam.T
it is the cleaned up one, in that you have repeated questions dat’s why it’s bulky
Hi
Please send me the link for dumps rahul.ibm@tiscali.co.uk
Thankyou guys .
For all those who still doubt the answer for question #1, an access port doesn’t use any vlan protocol, so the switch will not propagate vlan information at all. Switch A will not know the vlan for Switch B and visa versa and both will assume the local vlan so there will be no problem at all.
an isl frame will always have a tag, whereas a dot1q frame will have a tag except the frame assigned to the native vlan. An access port can only have one vlan assignment. It’s the vlan tag that gives the characteristic of a vitual local area network. The vlan tag identifies the ports in the vlan membership.
thus the difference in command formats
switchport access vlan [vlan number]
switchport trunk allowed vlan [vlan-list | all]
Took my exam today and passed. STP/LACP, MLS/EIGRP, and AAAdot1x labs, as well as HRSP Hotspot were on it. For LACP there were more requirements added like ensure that SWA and SWB having same STP mode and vlan 1, 21-23 must traverse trunk untagged. SWB does have vlan 99 name NativeTrunk created so I created the same on SWA and configured it on the channel ports, however, it is not supposed to traverse the trunk (in other words, it is not in the allowed vlan list). I recommend doing a “show running-config” to see what is already configured. Also, when I did a “show spanning-tree” both SWA and SWB showed itself to be the root bridge for the vlans. Also, it showed that one switch had spanning-tree ieee and the other rvst. Know this lab (amongst the others). When I remember more, I will post.
@V2- i am preparing for Switching exam and starting off fresh ( wrote CCNA in Nov,11). I followed Dynagen SIM previously but i am setting up my home lab with 3550′s and 28xx
Please guide me in preparing this exam.
Thanks in advance for your help. much appreciated.
This is a really funky question but interesting. Back to CCNA.
SB updates its arp table with PC1 data and assigns it to vlan 5, sourced from SB/Gi0
1) At startup the arp tables are empty.
2) PC1 pings (ICMP request) PC2
3) SA looks in its arp table no entry for PC2 ip
4) SA updates is arp table with PC1 data and assigns it to vlan 2
5) SA then broadcast an arp request (who owns this ip) to all its VLAN 2 ports
6) interface SA/Gi0 is in VLAN 2 forwards the arp request out its port
7) interface SB/Gi0 in vlan 5 receives an arp request
9) as a result request is broadcasted to all vlan 5 ports
10) PC2 is in vlan 5, source and destination data is swapped
11) the response is forwarded to SB/Gi0
12) SA receives the response
13) SA updates its arp table with PC2 data and assigns it to vlan 2, sourced from SA/Gi0
Here is the funky part
1) SB lists the source ip and source mac in the arp table from vlan 5 because it received the request from a port in vlan 5.
2) SA lists what was initially the destination ip and destination mac in the arp table from vlan 2 because it received the response from a port in vlan 2.
3) the switch is always looking to update it’s arp table.
vlan tagging in not involved because the initial request is a broadcast. Broadcast requests are only propagated to ports in its vlan. Because PC1 and PC2 are in the same subnet the ICMP request is successful.
SwitchA#show arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 10.10.10.1 164 0001.6434.5DCD ARPA Vlan2 -> PC1
Internet 10.10.10.2 – 0060.7075.CB2C ARPA Vlan2 -> SA
Internet 10.10.10.25 163 000A.4142.5C76 ARPA Vlan2 -> PC2
SwitchB#show arp
Protocol Address Age (min) Hardware Addr Type Interface
Internet 10.10.10.1 174 0001.6434.5DCD ARPA Vlan5 -> PC1
Internet 10.10.10.3 – 0001.420A.CA1E ARPA Vlan5 -> SB
Internet 10.10.10.25 175 000A.4142.5C76 ARPA Vlan5 -> PC2
last response is to question 1