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EIGRP OSPF Redistribution Sim

January 8th, 2015 in Lab Sim, LabSim Go to comments

Question

OSPF_EIGRP_Redistribution.jpg

Answer and Explanation:

First we need to find out 5 parameters (Bandwidth, Delay, Reliability, Load, MTU) of the s0/0/0 interface (the interface of R2 connected to R4) for redistribution :

R2#show interface s0/0/0

Write down these 5 parameters, notice that we have to divide the Delay by 10 because the metric unit is in tens of microsecond. For example, we get Bandwidth=1544 Kbit, Delay=20000 us, Reliability=255, Load=1, MTU=1500 bytes then we would redistribute as follows:

R2#config terminal
R2(config)# router ospf 1
R2(config-router)#
redistribute eigrp 100 metric-type 1 subnets
R2(config-router)#exit
R2(config-router)#router eigrp 100
R2(config-router)#redistribute ospf 1 metric 1544 2000 255 1 1500

(Notice: In fact, these parameters are just used for reference and we can use other parameters with no problem. Also, a candidate said that the simulator didn’t accept the Bandwidth of 1544; in that case, we can use a lower value, like 128.

If the delay is 20000us then we need to divide it by 10, that is 20000 / 10 = 2000)

Note: “usec” here does not mean microsecond (which is 1/1000 milliseconds) but means millisecond. In short usec = msec. I don’t know why they use the word “usec” here but just think it is “msec” (According to this link: http://www.cisco.com/en/US/tech/tk365/technologies_white_paper09186a0080094cb7.shtml#eigrpmetrics: “The delay as shown in the show ip eigrp topology or show interface commands is in microseconds”)

For R3 we use the show interface fa0/0 to get 5 parameters too

R3#show interface fa0/0

For example we get Bandwidth=10000 Kbit, Delay=1000 us, Reliability=255, Load=1, MTU=1500 bytes

R3#config terminal
R3(config)#
router ospf 1
R3(config-router)#
redistribute eigrp 100 metric-type 1 subnets
R3(config)#
exit
R3(config-router)#
router eigrp 100
R3(config-router)#
redistribute ospf 1 metric 10000 100 255 1 1500

Finally you should try to “show ip route” to see the 172.16.100.1 network (the network behind R4) in the routing table of R1 and make a ping from R1 to this network.

Note: If the link between R2 and R3 is FastEthernet link, we must put the command below under EIGRP process to make traffic from R1 to go through R3 (R1 -> R2 -> R3 -> R4), which is better than R1 -> R2 -> R4.

R2(config-router)# distance eigrp 90 105

This command sets the Administrative Distance of all EIGRP internal routes to 90 and all EIGRP external routes to 105, which is smaller than the Administrative Distance of OSPF (110) -> the link between R2 & R3 will be preferred to the serial link between R2 & R4.

A reader on our site has a closer explanation for the “distance eigrp 90 105” command so we quote it here for your reference:

The “distance” refers to the administrative distance of the routes provided by a given routing process. By default, internal (which means non-redistributed) EIGRP routes are given an administrative distance of 90 while external (redistributed from another routing process) EIGRP routes are given an administrative distance of 170. The default administrative distance of OSPF is 110. The administrative distance measures the “distance from the truth” and tells the router which routes are more trustworthy. Lower administrative distance = more trustworthy. For this reason, connected routes have an administrative distance of 0. They are the MOST TRUSTWORTHY, because they are physically connected to the router. When making a decision about which route to install in the routing table, the router looks at administrative distance first. The metric (or cost) is only considered if two routes have the same administrative distance.

In this case, R2 will learn about R4’s loopback network from both R4 and R3. The route from R4 will be in OSPF (admin distance of 110) because R2 is also running OSPF while the route from R3 will be an external EIGRP route (administrative distance of 170 by default). Since the OSPF route has a lower administrative distance, it will get placed in R2’s routing table and the R3-provided route will be ignored. This is not optimal, since the path through R3 is a faster, more reliable path. To fix this, we change the administrative distance of external EIGRP routes at R2 by using the “distance eigrp 90 105” command. This sets the administrative distance of internal EIGRP routes to the default of 90 and changes the administrative distance of external EIGRP routes to 105 (less than that of OSPF routes). Now, when R2 learns of the loopback network from R4 and R3, it will install the now lower administrative distance external EIGRP route from R3 and our traffic from R1 will take the faster path.

Note: Please check the OSPF process numbers first before typing these commands.

If you want to have a closer look at this sim and understand more about the “distance eigrp” command, please read my OSPF EIGRP Redistribute Lab in GNS3.

Other lab-sims on this site:

EIGRP Stub Sim

OSPF Sim

IPv6 OSPF Virtual Link Sim

EIGRP Simlet

Policy Based Routing Sim

Comments
Comment pages
1 3 4 5 26
  1. cloud9
    May 19th, 2017

    First Option(R1 -> R2 -> R3 -> R4):
    R1 to R2 BW = 1544Kbps
    R2 to R3 BW = 1544Kbps
    R3 to R4 BW = 100Mbps ( assuming its a fast ethernet link)
    TOTAL BW = 103.088Mbps

    Second Option (R1 -> R2 -> R4)
    R1 to R2 BW = 1544Kbps
    R2 to R4 BW = 1544Kbps
    TOTAL BW = 3.088Mbps

    One of the requirements is that all traffic must use the shortest path that provides the greatest BW.

    103.088Mbps is greater than 3.088Mbps which also means it’s much faster.

    Hope this helps!

  2. Chaka
    May 19th, 2017

    But all Serial links are the same bottleneck.
    So in my opinion it is not a better way but if it have to in the exam – OK.

  3. Blanco
    May 19th, 2017

    First serial is a bottleneck R1 to R2 BW = 1544Kbps so it does not make any difference that we would have FastEthernet with 100Mbs or another serial with 1544Kbps, since first one is always 1544Kbps and traffic can not go faster over it, no matter what is next. For me it makes no sense to manipulate that path.

  4. ANAroute
    May 21st, 2017

    Compilation of exams and including April and May.
    h t t p : / / c o r n e e y . c o m / q D 4 e y d
    the pass is
    !aAyefgyn-7nP18rSvGvzPPv5FJbO_e8AmeieWSZZtTk
    delete the spaces

  5. Anon
    May 22nd, 2017

    Hi Folks – I’m the Anon that asked the question (distance eigrp 90 105) in the first place.

    Took the exam and R1, R2, R3 are all connected via Fast Ethernet. The only serial link is R2 R4, so in the exam you will need to apply the final command.

    Cheers,
    Anon

  6. Anonymous
    May 27th, 2017

    pass ccnp route exam today…

  7. Anonymous
    June 2nd, 2017

    Anonymous – pls share you questions labs, drag and drop ? dumps stil valid ?

  8. Anonymous
    June 2nd, 2017

    pass4sure 229 q valid
    4 labs

  9. Anonymous
    June 2nd, 2017

    OSPF V3 Virvual link
    OSPF Evaluation
    Redistribution
    PBR
    OSPF V2

  10. razvan
    June 3rd, 2017

    Dear All ,
    Please can any one send to me the latest dump for CCNP routing (razvan_0072@yahoo dot com)

    Thank You

  11. Anonymous
    June 4th, 2017

    Dear All ,

    Please can any one send to me the latest dump for CCNP routing 229 q (suliman6620@gmali dot com)

    Thanks

  12. Hello
    June 19th, 2017

    Please can any one send to me the latest dump for CCNP routing 229 q (imnottechnical@ gmail . com)

  13. Anonymous
    June 20th, 2017

    Please can any one send to me the latest dump for CCNP routing 229 q ({email not allowed})

  14. 9tutUser
    June 30th, 2017

    Hello there
    I plan to give exam next week, can someone please send latest dumps or link to me.

    ismail_n (at) yahoo (dot)(com)

    Thank you in advance

  15. coloboy
    July 16th, 2017

    Took Route Exam today and passed. Several new questions but Labs were the same with just slight changes in IPs.

  16. aea_abbas@hotmail.com
    July 16th, 2017

    Dear All ,
    Please can any one send to me the latest dump for CCNP routing

    thank you

  17. atr
    July 17th, 2017

    @coloboy…what excatly labs were in the exam…thank you

  18. John
    July 18th, 2017

    can anyone send me the latest dump of CCNP switch and Route at nahid.hasan1 AT outlook dot com

  19. anhbt136
    July 26th, 2017

    Have any people have lastest dump CCNP route until now?

  20. Anonymous
    July 28th, 2017

    Please can any one send to me the latest dump for CCNP routing 229 q (johnoshea204@ gmail . com)

  21. JANE
    July 29th, 2017

    Quick question,
    I am going tru the redistribution lab
    Is it necessarily to define eigrp metrics during redistribution. What happens if it is definned under router sub command
    Router eigrp 100
    Default metric 1544, 20000, 255, 1 1500
    Thus ensuring that ospf picks it up via
    (redistribute ospf 1 metric) Only command
    Also, must the the metric type be 1

  22. daithidaithi
    August 3rd, 2017

    HI All taking my exam in a few days time – thanks Digitaltut for this resource

    so with this example i have asymetric routing and only one path takes shortest path that provides the greatest bandwidth.

    R1 to R4 goes via 2 > 4
    R4 to R1 goes via 4> 3>2>1

    any issue with this or am i over thinking it

  23. Cool_Dude
    August 14th, 2017

    @daithidaithi – please refer to the thread

    http://www.isisbeautyconcepts.com.au/?certs=share-your-route-v2-0-experience

    In Page – 161, you can find my inputs on this sim.

    Route from R1 to R4 is symmetric and

    Outbound : R1-R2-R3-R4
    Return : R4-R3-R2-R1

    R2’s EIGRP external routes’ ( Onle one external route) AD needs to be changed to a value less than 110 to make this symmetry work. [ distance eigrp 90 109 ]

    By the way, path’s bandwidth is not compounded but the least of all segments in the route, in this case R1 to R4 goes via 2 > 4 will only have 1.5M BW.

    Please correct me if I am wrong.

  24. Cool_Dude
    August 14th, 2017

    @daithidaithi

    Also below….

    In this case, R2 will learn about R4’s loopback network from both R4 and R3. The route from R4 will be in OSPF (admin distance of 110) because R2 is also running OSPF while the route from R3 will be an external EIGRP route (administrative distance of 170 by default). Since the OSPF route has a lower administrative distance, it will get placed in R2’s routing table and the R3-provided route will be ignored. This is not optimal, since the path through R3 is a faster, more reliable path. To fix this, we change the administrative distance of external EIGRP routes at R2 by using the “distance eigrp 90 105” command. This sets the administrative distance of internal EIGRP routes to the default of 90 and changes the administrative distance of external EIGRP routes to 105 (less than that of OSPF routes). Now, when R2 learns of the loopback network from R4 and R3, it will install the now lower administrative distance external EIGRP route from R3 and our traffic from R1 will take the faster path.

    http://www.isisbeautyconcepts.com.au/?certs=route-eigrp-ospf-redistribution-sim/comment-page-5#comment-1891462

    I am re-configuring the sim and will update any further inputs…but I reckon both the above will clear out most of your concerns.

  25. Flaw in Topology
    August 22nd, 2017

    I’m tracing from R4 to R1’s interface IP to R2…… Instead of R1 to R4’s loopback!!
    If you shut down the fast int between R3 and R2 causing the topology to reconverge from R4 thru R2… If Trace-route from R4 to R1’s interface facing R2.. It breaks. R2 seems to be unable to forward the packet to its adjacency “R1”
    However, R1 is able to ping/trace over to R4 loopback IP.
    Does anybody taken this lab this far? Any thoughts?

  26. Anonymous
    August 27th, 2017

    Full description how to configure MPLS :
    https://garziadmostafa.wordpress.com/

  27. ali
    August 27th, 2017

    how do we know that we should check int fa0/0 in router3

  28. Cool-Guy
    September 5th, 2017

    Hello,

    When configuring this lab my pc memory utilisation is full 100 % . Idle pc value is changed but that didn’t help either any thoughts.

  29. Anonymous
    September 12th, 2017

    dear all
    appreciate to send me the 100% valid dump in mail
    {email not allowed}

  30. kokwkz
    September 12th, 2017

    dears
    appreciate to send me dump 100% in my mail
    {email not allowed}

  31. Manoj
    September 16th, 2017

    If we get /26 route from OSPF and /28 route from EIGRP which route will be prefer?

  32. Manoj
    September 16th, 2017

    If one one host connected to two directly connected router then how packet will flow?

  33. Manoj
    September 16th, 2017

    What may be the reason if VTP not get propagated from one switch to another?

  34. Manoj
    September 16th, 2017

    Can OSPF will work if there is only one area say area 1 and there is no area 0?

  35. AhmedAl
    October 14th, 2017

    Please anyone can provide me the link for lab sim to download, also I tried to open with GNS VM show me there is error I have to convert anyone knows how to solve this problem
    advance thanks

  36. H-tech
    October 14th, 2017

    AhmedAl do you have latest dumb?

  37. fiddy
    October 15th, 2017

    Hi,

    I have tried to open route Exam sims in GNS v1.5.2 but after opening topology all nodes in the topology turned red , when I click over the node it says ” This node is not initialized”

    Can someone please know how to fix this so that I Can practice these exam labs ??

  38. AhmedAl
    October 15th, 2017

    H-tech
    No I have not da lastest

  39. CiscoDaddy
    October 16th, 2017

    Fiddy – recreate from site.. configs easy to get

  40. Spark
    October 27th, 2017

    please send latest dump to y o u n g s p a r k @ y m a i l . c o m thank you

  41. Chikku
    October 29th, 2017

    what are the labs in exam ?

  42. mac
    November 2nd, 2017

    on eigrp ospf redistribution sim
    is the txload and rxload is the load?

    MTU 1500 bytes, BW 1544 Kbit, DLY 20000 usec,
    reliability 255/255, txload 1/255, rxload 1/255

  43. nine
    November 5th, 2017

    on eigrp ospf redistribution, when do we apply this or not to apply this command?
    “distance eigrp 90 105”

  44. AS
    November 8th, 2017

    Hi
    I did redistribution task but still cannot ping 172.16.100.1 – what I am doing wrong ?

  45. shahab
    November 9th, 2017

    hello guys, I’m planning to study CCNP Routing in detail can someone please mail me the in-detail modules that would be helpful for me. my email is shahabkhanunderscore112atoutlookdotcom. thankx in advance

  46. dou
    November 19th, 2017

    noted

  47. Anonymous
    November 20th, 2017

    Please sent me the latest dump PFD file fjsuarez1981 @ yahoo dot com

  48. conip
    November 26th, 2017

    I believe redistribution from eigrp to ospf could be default E2 as fast ethernet would have metric 10 and serial 64

    so forwarding-metric from R4 perspective would always point to R3, so why to bother metric-type 1?

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