Home > IPv6 OSPF Virtual Link Sim

IPv6 OSPF Virtual Link Sim

May 8th, 2014 in Lab Sim, LabSim Go to comments

Question

TUT is a small company that has an existing enterprise network that is running IPv6 OSPFv3. However, R4’s loopback address (FEC0:4:4) cannot be seen in R1. Identify and fix this fault, do not change the current area assignments. Your task is complete when R4’s loopback address (FEC0:4:4) can be seen in the routing table of R1.

OSPFv3_IPv6_VirtualLink

Special Note: To gain the maximum number of points you must remove all incorrect or unneeded configuration statements related to this issue.

Answer and Explanation:

To troubleshoot the problem, first issue the show running-config on all of 4 routers. Pay more attention to the outputs of routers R2 and R3

The output of the “show running-config” command of R2:

OSPFIPv6v3VirtualLink_show_run_R2

The output of the “show running-config” command of R3:

OSPFIPv6v3VirtualLink_show_run_R3

We knew that 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,we can use a virtual link to connect to the backbone through a non-backbone area. The area through which you configure the virtual link is known as a transit area. In this case, the area 11 will become the transit area. Therefore, routers R2 and R3 must be configured with the area area-id virtual-link neighbor-router-id command.

+ Configure virtual link on R2 (from the first output above, we learned that the OSPF process ID of R2 is 1):

R2>enable
R2#configure terminal
R2(config)#ipv6 router ospf 1
R2(config-rtr)#area 11 virtual-link 3.3.3.3

(Notice that we have to use neighbor router-id 3.3.3.3, not R2’s router-id 2.2.2.2)

+ Configure virtual link on R3 (from the second output above, we learned that the OSPF process ID of R3 is 1 and we have to disable the wrong configuration of “area 54 virtual-link 4.4.4.4”):

R3>enable
R3#configure terminal
R3(config)#ipv6 router ospf 1
R3(config-rtr)#no area 54 virtual-link 4.4.4.4
R3(config-rtr)#area 11 virtual-link 2.2.2.2

We should check the configuration on R4:

R4>enable
R4#show running-config

You will see a wrongly configured virtual-link command. To get full mark we have to disable this command:

R4#configure terminal
R4(config)#ipv6 router ospf 1
R4(config-rtr)#no area 54 virtual-link 3.3.3.3

After finishing the configuration don’t forget to ping between R1 and R4 to make sure they work well!

Now all the configuration was done. It is weird that we can’t ping the IPv6 loopback interface of R4 (with the ping or ping ipv6 command) but we can check by using the command show ipv6 route on R1

The copying running-config startup-config command will not work but don’t worry, just skip it.

Notice: If you issue the command “show running-config” on R1, you will see these two lines:

passive-interface default
no passive-interface fa0/0 (fa0/0 is the interface connecting with R2)

These two lines make all the interfaces of R1 become passive interfaces except interface fa0/0. They are correctly configured so don’t try to disable them.

 

Other lab-sims on this site:

EIGRP Stub Sim

OSPF Sim

EIGRP OSPF Redistribution Sim

EIGRP Simlet
Policy Based Routing Sim

Comments
Comment pages
1 2 3 32
  1. AF
    January 15th, 2019

    @TutAdmin

    lab is not responding to
    R2#show running-config
    This command is not supported on this device.
    R2#

  2. AF
    January 15th, 2019

    @TutAdmin

    show run it staken the ful command is not.

    One more question is this correct? or should be Area 0 instead of 11?

    R1#sh run
    Building configuration…

    Current configuration : 794 bytes
    !
    interface Loopback0
    no ip address
    ipv6 address FEC0:1::1/64
    ipv6 ospf 1 area 11

  3. routaninja
    January 17th, 2019

    “After finishing the configuration don’t forget to ping between R1 and R4 to make sure they work well!”

    “Now all the configuration was done. It is weird that we can’t ping the IPv6 loopback interface of R4 (with the ping or ping ipv6 command) but we can check by using the command show ipv6 route on R1”

    In order to ping you have to advertise the loopbacks into ipv6 ospf process. Not sure if that is done on the exam. Will be taking it later this week.

  4. Shabooyma
    January 22nd, 2019

    Hello friends,
    can someone share the update dumps of CCNP RS 300-101

  5. SW
    January 22nd, 2019

    Hi Guys, Hope you are fine… Can you please assist me in order to get CCNP ROUTE dumps.

    smkwarsi(at)hotmail(dot)com

    Thanks in advance for the attention & consideration.

  6. Admiral
    January 22nd, 2019

    “It is weird that we can’t ping the IPv6 loopback interface of R4 (with the ping or ping ipv6 command) but we can check by using the command show ipv6 route on R1”

    Just assign an ipv6 address to the fa0/0 interface of R1 and ping will pass correctly.

  7. Anonymous
    January 25th, 2019

    Guys in the exam they did not ask to ping they just say:

    Your task is complete when R4’s loopback address (FEC0:4:4) can be seen in the routing table of R1.

  8. boomboom
    January 26th, 2019

    just a show ip route on R1 shall do it.

  9. Hagler
    February 14th, 2019

    Did anyone tried to do this one GNS3?
    Because in reality, at GNS3, if you remove area 54 virtual-link 3.3.3.3 it will not perform adjacency and R3 will not learn R4 loopback (FEC0:4:4).

    Any thoughts? ill still go with what digitaltut and everybody here experienced but would like to know if anyone saw it and explain what happened

    Thanks

  10. Andrew
    February 17th, 2019

    @hagler
    Same thing happened to me,
    unable to find R4 Loopback ip in R1 after removing area 54 command
    did u found any solution for this

Comment pages
1 2 3 32
  1. No trackbacks yet.