EIGRP Stub Sim
Question
By increasing the first distant office, JS manufactures has extended their business. They configured the remote office router (R3) from which they can reach all Corporate subnets. In order to raise network stableness and lower the memory usage and broadband utilization to R3, JS manufactures makes use of route summarization together with the EIGRP Stub Routing feature. Another network engineer is responsible for the implementing of this solution. However, in the process of configuring EIGRP stub routing connectivity with the remote network devices off of R3 has been missing.
Presently JS has configured EIGRP on all routers in the network R2, R3, and R4. Your duty is to find and solve the connectivity failure problem with the remote office router R3. You should then configure route summarization only to the distant office router R3 to complete the task after the problem has been solved.
The success of pings from R4 to the R3 LAN interface proves that the fault has been corrected and the R3 IP routing table only contains two 10.0.0.0 subnets.
Answer and Explanation:
First we have to figure out why R3 and R4 can not communicate with each other. Use the show running-config command on router R3
Notice that R3 is configured as a stub receive-only router. The receive-only keyword will restrict the router from sharing any of its routes with any other router in that EIGRP autonomous system. This keyword will also prevent any type of route from being sent.
Therefore we will remove this command and replace it with the eigrp stub command:
R3#configure terminal
R3(config)#router eigrp 123
R3(config-router)#no eigrp stub receive-only
R3(config-router)#eigrp stub
R3(config-router)#end
Now R3 will send updates containing its connected and summary routes to other routers. Notice that the eigrp stub command equals to the eigrp stub connected summary because the connected and summary options are enabled by default.
Next we will configure router R3 so that it has only 2 subnets of 10.0.0.0 network. Use the show ip route command on R3 to view its routing table
R3#show ip route
Because we want the routing table of R3 only have 2 subnets so we have to summary sub-networks at the interface which is connected with R3, the s0/0 interface of R4.
There is one interesting thing about the output of the show ip route shown above: the 10.2.3.0/24, which is a directly connected network of R3. We can’t get rid of it in the routing table no matter what technique we use to summary the networks. Therefore, to make the routing table of R3 has only 2 subnets we have to summary other subnets into one subnet.
In the output if we don’t see the summary line (like 10.0.0.0/8 is a summary…) then we should use the command ip summary-address eigrp 123 10.2.0.0 255.255.0.0 so that all the ping can work well.
In conclusion, we will use the ip summary-address eigrp 123 10.2.0.0 255.255.0.0 at the interface s0/0 of R4 to summary.
R4>enable
R4#configure terminal
R4(config)#interface s0/0
R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.0.0
Now we jump back to R3 and use the show ip route command to verify the effect, the output is shown below:
(But please notice that the ip addresses and the subnet masks in your real exam might be different so you might use different ones to solve this question)
But in your real exam, if you see the line “10.0.0.0/8 is a summary,….Null0″ then you need to summary using the network 10.0.0.0/8 with the command “ip summary-address eigrp 123 10.0.0.0 255.0.0.0″ . This configuration is less optimize than the first but it summaries into 2 subnets as the question requires (maybe you will not see this case, don’t worry!).
The command “copy running-config startup-config” will not work so try using this command; just skip if it doesn’t work.
Other lab-sims on this site:
EIGRP Simlet
Policy Based Routing Sim
Got 100% in this lab. EVERYTHING MENTIONED in the configuration is correct. for two subnets use
ip summary-address eigrp 123 10.0.0.0 255.0.0.0. and donot waste time in reading older blogs. Should check what digitaltut update is.
surajit, digitaltut has updated that the ip summary-address eigrp 123 10.0.0.0 255.0.0.0
as the IP 10.2.3.0/24, which is a directly connected network of R3, there fore
R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.0.0.
Did u encounter this in ur lab today.
Inputs will be greatly appreciated.
yes
the Question in the lab was demanding two subnets. So i used
ip summary-address eigrp 123 10.0.0.0 255.0.0.0
on the routing table of R3-sh ip route will show two subnetworks
10.0.0.0/8 via 10.2.3.4
and 10.2.3.0/24 directly connected
Why not “#ip summary-address eigrp 123 10.2.2.0 255.0.0.0″ this also on S0/0 on Router-4 ?
Fellas,
I tried this topology on my emulator and what I found is summary address for subnets 172.16.0.0/16 on Null0 and again another 10.0.0.0/8 to Null0 again. I couldn’t decide whether the 10.0.0.0/8 to Null0 will make my configuration invalid because of the 2 subnets of 10.0.0.0 requirement. Please somebody comment on this! I will take the exam this week.
@urFriend
The 10.0.0.0/8 to Null0 should only appear on R4. Since R3 is the router that needs 2 subnets then you should be fine. Remember the summary address goes on R4; not R3.
Where can I DL CCNP-ROUTE sims .pkt files?
Howdy, I used the ip summary-address eigrp 123 10.0.0.0 255.0.0.0 on R4 but the routing table on R3 still shows an entry to null0, not just that, but I’m not able to ping from R3 back to 10.2.9.2 (loopback on R2). If I do “no auto-summary” on R3 and “ip summary-address 10.2.0.0 255.255.0.0″, the pings work again and I get the routing table shown below…….comments?
Gateway of last resort is not set
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, FastEthernet0/0
10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks
D 10.2.0.0/16 [90/2172416] via 10.2.3.4, 00:00:05, Serial1/0
C 10.2.3.0/24 is directly connected, Serial1/0
C 10.2.3.4/32 is directly connected, Serial1/0
Hey Guys
Can anyone confirm whether these labs are for the ROUTE exam?
i wote BSCI in July, and i got the very same labs
please advice as i will be writing the route exam soon as well
there is a new redistrubution lab in the 713 dumps,. eigrp-isis
The 10.2.0.0 255.255.0.0 is an excellent summary however I think the best summary is 10.2.0.0 255.255.240.0
correct me if I am wrong.
Yes I agree with TEE
You advertise eigrp routes as they are leaving router 4 serial 0/0 interface
either you change mask to /8 or 16/ you full fill the task list : Next we will configure router R3 so that it has only 2 subnets of 10.0.0.0 network !
first network 10.0.0.0 /8 or /16 learned by eigrp
second network is the connected serial interface wich was assigned 10.2.3.3 so network 10.2.3.0 /24
In real life best summarization is always prefered !
So in this test, my running-config on R3 shows a 10.0.0.0 /8, i am going on R4 serial 0/0 and advertise eigrp routes as they leaving serial interface 0/0 with the /8 (no risk at all) !
In this task we assume that you know summarization (ccna), test is where to go to do it and of course how !
I build this Topology in GNS and make R3 stup receive only so i do show ip route in R3 and showed all routes in this topology (R4,R3) after that i do ping for all route showed and successed before remove the stup receive only from eigrp process.
My Question Why all routes show and all routes successes before remove eigrp stub and Summary????????????????
Hi Guys
I am preping for my MPLS 642-611 exam. Can someone please point me to the right directions for dumps / labs. I have old dumps but i have no idea how exam labs looks like. Any help will be great.
Thanks.
babo /
R3 receive all the routes from R2, R4 (R3 stub receive only) but R3 is not advertising routes
Did you check R2 and R4 ip route to see if the network 172.16.1.0 /24 is listed in ? if it is the case your gns3 lab has a problem :)
R3 is acting like a tightwad, a miser etc. (thanks R2, R4 for advertising routes, i take, but me R3 i don’t have any route to advertise !)
can i use this on r4?
r4>enable
r4#configure terminal
R4(config)#interface so/o
R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.0.0
Hi
I would like to know if we can use :R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.240.0
can any one tell me how can i download this lab / sim
plzzzzzz help me
I have made all of the 642-902 Test sims in a GNS3 format, just email if you want a copy at cciersbound@yahoo.com
Later,
CCIERSBound
dont forget to type no auto-summary on each router
Today i pass got this lab its same i use passguide 3.27 vce
Lads,
In my belive it should be summarized like this:
————————————————————————————-
Network 1: C 10.2.3.0/24
Network 2: D 10.2.0.0/20
R4 S0/0:
R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.240.0
————————————————————————————-
You can use /16 and /8 but it is not best practice I presume. My only concern do Cisco want us to summarize route on R3 (10.2.3.0/24 -> 10.2.0.0/21 or easy 10.2.0.0/16)???
This part “configure route summarization only to the distant office router R3″ tell us to summarize outisde R3. Am I right?
Yes, you are right, because i just have calculated the summary route. i am getting the same subnet mask.
Please can any one answer my question,
What if i will be asked to ping R3 from R2 LAN interface????
Is anyone cleared ROUTE recently…please which is valid dumps
hi all
i have passed yesterday with score 966/ 1000
the passguide 3.37 is valid with 95 %
thank to digital tut and to everybody
this site is really great
I keep getting the following on R3:
10.0.0.0/8 is variably subnetted, 3 subnets, 3 masks
D 10.2.0.0/16 [90/2172416] via 10.2.3.4, 00:00:02, Serial1/0
C 10.2.3.0/24 is directly connected, Serial1/0
C 10.2.3.4/32 is directly connected, Serial1/0
Nowhere am I advertising 10.2.3.4 with 0.0.0.0, how come I keep on seeing three subnets?
Nevermind, putting on encap ppp on back2back routers add extra entry in the routing table. After removing that, I got 2 subnets.
—————–
R3 Conf:
—————
router eigrp 123
network 10.2.0.0 0.0.255.255
network 172.16.1.0 0.0.0.255
no auto-summary
eigrp stub
—————————-
Routing table:
—————————
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Loopback0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 10.0.0.0/8 [90/2172416] via 10.2.3.4, 00:07:20, Serial1/0
C 10.2.3.0/24 is directly connected, Serial1/0
———————–
R4 Conf:
———————-
interface Serial0/0
ip address 10.2.3.4 255.255.255.0
ip summary-address eigrp 100 10.0.0.0 255.0.0.0
You have to issue no auto-summary on R3 , otherwise the 10.* subnets will be blackholed
R3
router eigrp 123
network 10.0.0.0
network 172.16.0.0
no auto-summary
eigrp router-id 3.3.3.3
eigrp stub connected summary
R3#show ip route
172.16.0.0/24 is subnetted, 1 subnets
C 172.16.1.0 is directly connected, Loopback0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 10.2.0.0/20 [90/2195456] via 10.2.3.4, 00:03:53, Serial0/0
C 10.2.3.0/24 is directly connected, Serial0/0
R4
interface Serial0/0
ip address 10.2.3.4 255.255.255.0
ip summary-address eigrp 123 10.2.0.0 255.255.240.0 5
router eigrp 123
network 10.0.0.0
no auto-summary
eigrp router-id 4.4.4.4
This is the right summary address : 123 10.2.0.0 255.255.240.0 { using /20 bit mask }
so
This is the right summary address : 10.2.0.0 255.255.240.0 { using /20 bit mask }
..The Enha nced Interior Gateway Routing Protocol EIGRP Stub Routing feature improves network stability reduces resource utilization and simplifies stub router configuration….. ..When using the EIGRP Stub Routing feature you need to configure the distribution and remote routers to use EIGRP and to configure only the remote router as a stub.
Where can i get the GNS lab so i can practice ? or just have to byheart the commands ??
Can anyone explain abt ip summary-address eigrp 123 10.2.0.0 255.255.0.0
my question is 10.2.0.0/24 means class c then why we are using subnet as 255.255.0.0
Appreciate if someone could help
@riya
that is the purpose,honey. if u are using 255.255.0.0 means that you advertise this whole 16 bits as class B range.
10.2.2.0
10.2.3.0
bla bla bla until
10.2.9.0
it all can be summarized at
10.2.0.0 255.255.0.0 —– 10.2.0.0 11111111.11111111.00000000.00000000
or
10.2.0.0 255.255.240.0 —– 10.2.0.0 11111111.11111111.11110000.00000000.
You need to see the “1″ bit shown,darling and check if those 10.2.2.0 until 10.2.9.0 meets the summarization…
Really stupid question but where exactly does eigrp stub come in? As in, under which topic? I’m not able to find it.
Under EIGRP. No hard configurations.
if you took your route exan in 2011 pls let me lnow what sims or labs where on exam plsssssssssssssss. How man labs are in exam
@AW311 plsssssssssssssss read ROUTE FAQs & Tips section of this very website.
anyone tried ping R3 lan interface from R4? Does it works?
Hi frndz , i sheduld my route exam on monday 24 jan 11 .i hope my digitaltut frnd’z full support. 1 month ago i wrote tshoot i got 1000/1000. Reply me ur valuable openion
realsherifka@yahoo.co.in
Thanks 2. Include me also in ur pray
is the ” ip summary-address eigrp 123 10.2.0.0 255.255.0.0 ” the same as in the exam….?
is the exam also the same: ip summary-address eigrp 123 10.2.0.0 255.255.0.0
Hi Guys,
I am litttle confused here ,should i use
ip summary-address eigrp 123 10.2.0.0 255.255.0.0 or
ip summary-address eigrp 123 10.2.0.0 255.255.240.0
because when i summarize 10.2.0.0-10.2.0.9
i get 10.2.0.0/20 and subnet mask 255.255.240.0,can any1 pls advise?
@ Swetha
If you use mask 255.255.0.0 you are advertising the whole class B block which is not wrong but not the most optimized summary, because that way R4 will advertises 10.2.0.0 – 10.2.255.0 although it only knows about 10.2.2.0-10.2.9.0 networks.
But if you use 255.255.240.0 mask. R4 will advertise only 10.2.0.0 – 10.2.15.0 networks only. Which is more specific than the previous case.That is the only difference.
In both cases, the routing table will have 2 subnets, so no harm done and both methods will follow the required criteria.
But personally I use 255.255.240.0 because that’s the best practice.
Hope this helps.
@ Sham:Thanks a lot i got your point .
any tips on what will be use now?
255.255.0.0 or 255.255.240.0?
Can anyone please tell me if IS-IS is in the exam 642-902 ROUTE or not ?
no its not its outdated….
its not included in new syllabus……
check if there is “no auto-summary” configured on R3, if not configured , the route tabel of R3 will have a NULL interface.
turn off auto-summary on R3 to make the result right.
I m heading to give my 642-902 ROUTE now……
Good luck Yogesh, share us some of the LAB REQUIREMENTS
Good luck Yogesh, share us some of the LAB REQUIREMENTS you got in your exam
someone please tell me how can I practice/download the Lab Sims before I sit for the real exam recently…eagerly waiting for a reply
Thanks in advance
Regarding to the most specific summary:
The most specific for 10.2.2 and 10.2.3 networks, mask 255.255.248.0 is the best…not 255.255.240.0….
The most specific for 10.2.2 and 10.2.3 networks, mask 255.255.252.0 is the best …not 255.255.248.0
Range of 255.255.252.0 = 10.2.0.1 to 10.2.3.254
Even better 255.255.254.0
range from 10.2.2.1 to 10.2.3.254
the problem is that we have to summarize routes from 10.2.2.0 to 10.2.9.0 included.
255.255.248.0 let outside 10.2.8.0 and 10.2.9.0 so the best mask remain
255.255.240.0
Since i’m studing and i want to make some practice, i would like to solve this lab without reading the solution first… do you have the configurations of the routers? so that i can load them on my lab and than try to solve it?
thanks
Please can anyone help send me the testinside for the Route exam. This is my e-mail stanleos2000@yahoo.com.
Otherwise any other valid dumps.
Thanks.
Just kilt it 3/30/2011. This wasnt featured lol
If you miss “no auto-summary” on R3, you have to write on R4 “ip summary-address eigrp 1 10.0.0.0 255.0.0.0″, and if you have “no auto-summary” on R3, write “ip summary-address eigrp 1 10.2.0.0 255.255.0.0″. When you miss “no auto-summary” on R3, in the routing table is a appear “D 10.0.0.0/8 is a summary, 00:00:16, Null0″.
please can some one help me to send me the route exam to this email anoma_84@yahoo.com thanks
Thanx digitaltut
iam looking for job in routing.I done CCNA certification,CCIP with good knowledge of routing
If do you have any vancy then please send on my E-mail id
swapnil_keer@rediffmail.com
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I did my route exam yesterday and thank God i passed 941/1000…the dorms and labs are still valid. Thanks Gogy, thanks Digitaltut…
Ahmed
hai guys,
I need a clarification in this Lab i need to give the command ip summary-address eigrp 123 10.2.0.0 255.255.0.0 or ip summary-address eigrp 123 10.0.0.0 255.0.0.0 in the Exam. plz help me i planed to write the exam on Monday
just write ip summary-address eigrp 123 10.2.0.0 255.255.0.0
http://ciscocertindia.blogspot.com/2011/04/latest-pass4sure-ccnp-642-902-route.html
Hi, is it possible to use “?” on all labs, just in case I forgot the exact syntax of command…thanks.
ip summary-address eigrp 123 10.2.0.0 255.255.0.0. and ip summary-address eigrp 123 10.2.0.0 255.0.0.0.which one is OK?
Anything that covers the range works for me in GNS3 for the summary.
please what dumps is good for my preparation towards my bsci exams this month?
Why you summarize 10.2.0.0 and not you sumarize 10.2.2.0 with a mask that contain all the networks?
Regards
sorry i have read another posts and i have read 10.2.0.0/16 its valid.
I have a doubt…
¿Its necessary to put no auto summary in R3 or its included in the router config?
Thanks ¡¡
Hi Guys: I have tested all the points you mentioned in comments session. I used GNS3 with 3660 route’s IOS
Note
Point1: I the auto-summary is turn on and you configured “ip summary-address eigrp 10.0.0.0 255.0.0.0″ in R4 then it will solve to show 2subnets problem.
R3#show ip route eigrp
172.16.0.0/16 is variably subnetted, 2 subnets, 2 masks
D 172.16.0.0/16 is a summary, 00:05:38, Null0
10.0.0.0/8 is variably subnetted, 2 subnets, 2 masks
D 10.0.0.0/8 is a summary, 00:03:57, Null0
But this how can R3 will find the route to R2′s route , no way. But R2–>R4–>R3–>172.16.0.0/24 is in the routing table of R2 R4 R3
SO YOU MUST NEED TO DISABLE “AUTO-SUMM” option in EIGRP of R3. Otherwise R3–>R4–>R2 routes will be failed
Points 2: If AUTO-SUMM option is disabled in R3 then you can use
“ip summary-address eigrp 10.2.0.0 255.255.240.0″ in R4. It works fine and must be the best summary address for R4
Configuration file can found here
hxxp://www.4shared.com/document/CdRPFApF/EIGRP_STUB_SIMAzim.html
BR//
Azim,
Correction please:
Point1: auto-summary is turn on in R3 and ou configured “ip summary-address eigrp 10.0.0.0 255.0.0.0″ in R4 then it will solve to show 2subnets problem.
SORRY for BAD ENGLISH, hope you will understand what i want to say ,, (‘.’)
Azim, in the first point ip summary-address eigrp 10.2.0.0 255.255.0.0 its not better, it not works?
ok, i have read al the post.
The best is in R3 to put no auto-summary and sumarize the 10.2.0.0 255.255.240.0 in R4 . ITs ok?
@batman May 15th, 2011:
in R3 to put no auto-summary and sumarize the 10.2.0.0 255.255.240.0 in R4
It works perfect in real IOS of CISCO 3660.
Great information! I’ve been looking for something like this for a while now. Thanks!
pls can someone assist me with the latest dumps for route exam, my exam is two weeks time
email: seoul.child@yahoo.com .
Thanks all for ur usual support.
@ahmed pls cud u send me the dunmps u used for the exam.
Thank
Email: seoul.child@yahoo.com
Has Anyone seen this lab on the exams recently
It appears the 4 labs on majority of posting are
Labs: IPv6 OSPF, PBR, EIGRP-OSPF Redistribution, OSPF Stub
pls can someone assist me with the latest dumps for route exam,
email: shadab_iqbal@hotmail.com
Thanks
check from IPv6 OSPF Virtual Link site.
Please can any one send my on my e-mail GNS3 laba and initial configurations
eng_ganna2008@yahoo.com
Because my test will be after tomorrow isA
thanks in advance
R4(config-if)#ip summary-address eigrp 123 10.2.0.0 255.255.0.0
(OR)
R4(config-if)#p summary-address eigrp 123 10.0.0.0 255.0.0.0
PLEASE Tell the correct Command for this Scenario..I am writing exam on 27th Exam
Both commands will work, but remember that the routing table prefers routes with more matching bits so try and be as specific as possible.
#############
hi all.
the questions says….
“”You should then configure route summarization only to the distant office router R3 “”
——————————————-
which means that the ip summary-address eigrp 123 10.2.0.0 255.255.240.0 must be entered in R4 and not R2
Yes, configure summarisation on R4, so this summary route is ONLY passed to R3.
@uddika June 26th, 2011
the configuration is on R4 if you were following
Hi everyone,
I passed 642-902 with 930 on 16/7/2011 . I used Test inside v 6.28 and all Q and Labs were from it without any change even IP addresses.you can download it from http://www.4shared.com/document/rjXsxC69/642-902V628.html.
-Best for All
Thanks Ahmed,
Is there any IS-IS questions included in the exam? Please everyone i would like to know about it.
Thanks
Thanks Ahmed for the info and congratulation for your success … keep the good work!!!
Is there any IS-IS questions included in the exam? Please everyone i would like to know about it.
Thanks
hailux, no multicast,dhcp and is-is
Thank you dear… you saved my time.