Home > EVN & VRF Questions

EVN & VRF Questions

July 21st, 2017 in ROUTE 300-101 Go to comments

Quick review:

Easy Virtual Network (EVN) is an IP-based network virtualization solution that helps enable network administrators to provide traffic separation and path isolation on a shared network infrastructure. EVN uses existing Virtual Route Forwarding (VRF)-Lite technology to:
+ Simplify Layer 3 network virtualization
+ Improve shared services support
+ Enhance management, troubleshooting, and usability

Question 1

Explanation

All the subinterfaces and associated EVNs have the same IP address assigned. In other words, a trunk interface is identified by the same IP address in different EVN contexts. EVN automatically generates subinterfaces for each EVN. For example, both Blue and Green VPN Routing and Forwarding (VRF) use the same IP address of 10.0.0.1 on their trunk interface:

vrf definition Blue
vnet tag 100
vrf definition Green
vnet tag 200
!
interface gigabitethernet0/0/0
vnet trunk
ip address 10.0.0.1 255.255.255.0

-> A is correct.

In fact answer B & C are not correct because each EVN has separate routing table and forwarding table.

Note: The combination of the VPN IP routing table and the associated VPN IP forwarding table is called a VPN routing and forwarding (VRF) instance.

Question 2

Explanation

EVN is supported on any interface that supports 802.1q encapsulation, for example, an Ethernet interface. Instead of adding a new field to carry the VNET tag in a packet, the VLAN ID field in 802.1q is repurposed to carry a VNET tag. The VNET tag uses the same position in the packet as a VLAN ID. On a trunk interface, the packet gets re-encapsulated with a VNET tag. Untagged packets carrying the VLAN ID are not EVN packets and could be transported over the same trunk interfaces.

Reference: http://www.cisco.com/c/en/us/products/collateral/ios-nx-os-software/layer-3-vpns-l3vpn/whitepaper_c11-638769.html

Question 3

Explanation

An example of using “autonomous-system {autonomous-system-number}” command is shown below:

router eigrp 100
address-family ipv4 vrf Cust
net 192.168.12.0
autonomous-system 100
no auto-summary

This configuration is performed under the Provide Edge (PE) router to run EIGRP with a Customer Edge (CE) router. The “autonomous-system 100” command indicates that the EIGRP AS100 is running between PE & CE routers.

Question 4

Question 5

Question 6

Explanation

EVN builds on the existing IP-based virtualization mechanism known as VRF-Lite. EVN provides enhancements in path isolation, simplified configuration and management, and improved shared service support

Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/evn/configuration/xe-3s/evn-xe-3s-book/evn-overview.html

Maybe the “improved shared services support” term here implies about the support of sharing between different VRFs (through route-target, MP-BGP)

Question 7

Explanation

This question is not clear because we have to configure a static route pointing to the global routing table while it stated that “all interfaces are in the same VRF”. But we should understand both outside and inside interfaces want to ping the loopback interface.

Question 8

Explanation

EVN supports IPv4, static routes, Open Shortest Path First version 2 (OSPFv2), and Enhanced Interior Gateway Routing Protocol (EIGRP) for unicast routing, and Protocol Independent Multicast (PIM) and Multicast Source Discovery Protocol (MSDP) for IPv4 Multicast routing. EVN also supports Cisco Express Forwarding (CEF) and Simple Network Management Protocol (SNMP).

Reference: http://www.cisco.com/c/en/us/td/docs/ios-xml/ios/evn/configuration/xe-3s/evn-xe-3s-book/evn-overview.html

Question 9

Explanation

Route-target is is tagged to each VPN when it is exported. In other words, when a prefix is exported with a route-target, an extended BGP community is attached to that prefix. If this community is matched with the (import) route-target of the receiving side then the prefix is imported to the receiving VRF.

Question 10

Explanation

Easy Virtual Network (EVN) is an IP-based virtualization technology that provides end-to-end virtualization of two or more Layer-3 networks. You can use a single IP infrastructure to provide separate virtual networks whose traffic paths remain isolated from each other.

An EVN trunk interface connects VRF-aware routers together and provides the core with a means to transport traffic for multiple EVNs. Trunk interfaces carry tagged traffic. The tag is used to de-multiplex the packet into the corresponding EVN. A trunk interface has one subinterface for each EVN. The vnet trunk command is used to define an interface as an EVN trunk interface.

In other words, EVN trunk interfaces allow multiple VRFs to use the same physical interfaces for transmission but the data of each VRF is treated separately. Without EVN trunk interfaces we need to create many subinterfaces. Therefore virtual network trunk (VNET) decreases the network configuration required.

Note: There is no “Easy Trunk” component or technology.

Comments
  1. Jonny
    July 26th, 2016

    I guess question 1 is asking about the characteristic/features shared.
    So it does not means that the physical routing/forwarding table share.

    Think the person who set this question want to test on the trunk interface, which was indirectly mentioned with sub-interfaces and inheritance? (my guess)

    Anyway this is what I think and I am still pursuing my CCNP :P

  2. hydra
    July 29th, 2016

    pls how get ques.

  3. cls
    August 13th, 2016

    Can anyone explain Q7 I am confused.

  4. NP`
    September 1st, 2016

    Q1 D, E – ACL and Netflow are not supported by EVN trunk, so also not supported by subinterface, then not supported status is shared from trunk to subinterfaces :-)

  5. Anonymous
    September 10th, 2016

    thank u digital tut

  6. kk
    September 19th, 2016

    thanks Fein

  7. Goofball
    October 4th, 2016

    Guys, I failed today with a 640. The ‘300-101: Implementing Cisco IP Routing’ exam is completely different then what is on this site. Not even close. There are maybe 10 questions that are the same… What happened???

  8. ok2
    October 11th, 2016

    I don’t see the questions anymore. what is going on?

  9. bdaboy22
    October 18th, 2016

    Can anyone verify Goofball’s comment? I have to re-certify my CCNP by the end of month.
    Tx

  10. QQ
    November 14th, 2016

    Everything you require to get ready and quickly pass the tough Cisco Certified Design Professional 300-101exam with 100% valid questions answers & pass guarantee in first attempt. http://www.grades4sure.com/300-101-exam-questions.html

  11. Anna
    November 17th, 2016

    I passed the written exam by scoring 90%. Most of the questions are from the http://www.testmayor.com dumps, though the sequences of choices are changed, so it is better to understand the concepts beforehand and go through the dumps so that you will not be surprised in the exam.

  12. J
    February 3rd, 2017

    Just took the 300-101 8xx/1000 used nothing but 149q and Tagwa 49. So here is what I saw on the test, but didn’t see in either of those study guides.

    1. IP SLA configuration and general knowledge
    2. Several PPPoE questions
    3. Numerous queries about NAT (time-range)

    Bottom line: If you have a clue plus know digitaltut, 149q and Tagwa 49 you will Pass!

    Good Luck Gents

  13. Anonymous
    February 5th, 2017

    Anyone know the answer to q1 for certain? At this URL, it notes that Netflow and ACLs are not supported on an EVN trunk. So that leaves us with answers A, B, and C. However, the answer given say taht answer B and C aren’t correct. So, wtf???

    https://www.cisco.com/en/US/docs/ios-xml/ios/evn/configuration/xe-3sg/evn-overview.pdf

  14. Martin
    February 6th, 2017

    @ J where did you get Tagwa 49? It seems I can’t find it anywhere. I only have 41.

  15. flyingtuvi
    February 7th, 2017

    Congrats J and thanks for sharing the dumps to focus on. I am taking 300-101 in 3 days and will let you know how I go. I have tagwa and 149q

  16. Anonymous
    February 18th, 2017
  17. mirzokhid
    February 28th, 2017

    hello everyone, can anyone share with me also tagwa. Please send to ahilles05 -dot- 94 @ gmail -dot- com. Thank you in advance.

  18. Anonymous
    March 8th, 2017

    Passed! used tut questions and free dumps from https://drive.google.com/open?id=0B5mAFqgydmCzTGd0VU9nQVZEaEE

  19. ronin
    April 21st, 2017

    Question number 1 seems to say the answer is A,B,C but then the explanation states that B&C are wrong and only A is correct when the question asks us to pick 3. Plus the (?) threw me.
    ej

  20. Anonymous
    June 30th, 2017

    Hello..
    can u guys please send me the latest dumps on miguelfilipe_20_01 @ hotmail . com

  21. Ray
    July 2nd, 2017

    Please can someone please send the dumps to me at

    {email not allowed}

    Very much appreciated

  22. Ray
    July 2nd, 2017

    Please can someone send the recent dumps to me

    rayvgreen1 @ gmail . com

    Thank You much!

  23. zvekuba
    July 7th, 2017

    can someone send recent dumps to zvekuba @ gmail . com

  24. E.T.
    August 7th, 2017

    Q7 correct answers should be:

    – add the loopback to the vrf
    – add dynamic routing and advertise the loopback. //obviously for the vrf, but this is the closest to a correct answer and is implied by the “local OR REMOTE” statement

    The whole point of VRFs is isolation from the global routing table…Should you want to-for whatever reason-create static routes those should be created both in the global routing table AND in the vrf table.

  25. dapo
    August 24th, 2017

    Hi E.T.,

    I agree with you. But ‘adding a static route for the VRF that points to the loopback interface’ on R2 would be easier and quicker. I think.

  26. dapo
    August 26th, 2017

    Hi E.T. and all,

    After 2nd thought, I think the ‘static route’ statement’s wording is not right. To use a static route, the wording should be ‘adding a static route for the loopback interface, that points to the appropriate next hop IP address, for the VRF on R2’.

  27. failed
    September 14th, 2017

    lots of new questions. no new sim.. eigrp, ospf verification, redistribution sim, and pbr sim. three new drag and drop, memorize the whole answers here their answers are shortened.. good luck i am taking another exam next week and am trying to practice again here if not i will have to find another source..

  28. Ip nam
    October 14th, 2017

    Where is the questions ? Hello there is just the answer

  29. Fabian
    November 9th, 2017

    Scored 9xx, used dumps from IT-Libraries. You can find them on the net for free or in the comments here.

  30. durshen
    November 11th, 2017

    Hi friends, I have the valid dump with me and I’m wiling to share. Please contact me via durshen81 @ gmail .com

  31. Archie
    November 14th, 2017

    Smashed my route exam today, 9xx used the dumps from it libraries and tut.

  32. Tyler
    November 21st, 2017

    Passed, if you go the exam study the 539q dumps.

  33. jay
    November 23rd, 2017

    where are the 539q dumps

  34. Freeman
    November 28th, 2017

    Passed, you can find part of the questions from the exam in this dumps https://drive.google.com/open?id=0B5mAFqgydmCzVWtzU09fYV9SZGc

  35. Milton
    November 28th, 2017

    Passed today, used the 440q dumps from IT-Libraries . you can find them for free with a google search

  36. Kendall
    November 28th, 2017

    Passed today, used the 539q dumps.

  37. Frank
    December 4th, 2017

    Confirming the 21q dumps are valid.

  1. No trackbacks yet.