10-16-2012 04:12 AM - edited 03-04-2019 05:52 PM
Hi Experts ,
I have created one lab to understand LSA 5 & LSA 4 in better manner.....
If you look at my topology , i have configured ospf and eigrp redistribution on R2 and injected LSA 5 into Area 1 .....
Now , if i want to reach R6 routes from R3 router , it goes via ABR router R1 > R2 > R6 however i want to manupulate route such a way that , To reach R6 from R3 , it should go via R4 > R6
But i am unable to find an option to do this ....
Even I tried to chage the cost value on R3 / Ethernet 0/1 interface to 100 , it goes via R1 only ......
Could you please suggest me on this .... i am working on this lab since long time without getting any soln.
It would be really helpful for me to understand this .......
Solved! Go to Solution.
10-16-2012 04:25 AM
Hello,
Recall that in OSPF, inter-area traffic must go through the backbone. The connection between R3 and R4 is, according to OSPF rules, illegal - it connects two non-backbone areas together. As a result, OSPF will not consider this link in the path calculation. So in other words, without modifying your topology or configuring virtual links, it is not possible to accomplish your goal of routing through the R3-R4-R2-R6 path.
A possible solution would be to configure a virtual link between R1 and some other router, say, R4. However, this complicates things and does not really make the goal of understanding LSA-4 and LSA-5 simpler.
Perhaps the easiest modification of your network to see the working of LSA-4 and LSA-5 would be as follows:
Renumber the existing Area 25 to Area 0
Renumber the existing Area 0 to Area 2
Leave the existing Area 1 as is
Best regards,
Peter
10-16-2012 04:25 AM
Hello,
Recall that in OSPF, inter-area traffic must go through the backbone. The connection between R3 and R4 is, according to OSPF rules, illegal - it connects two non-backbone areas together. As a result, OSPF will not consider this link in the path calculation. So in other words, without modifying your topology or configuring virtual links, it is not possible to accomplish your goal of routing through the R3-R4-R2-R6 path.
A possible solution would be to configure a virtual link between R1 and some other router, say, R4. However, this complicates things and does not really make the goal of understanding LSA-4 and LSA-5 simpler.
Perhaps the easiest modification of your network to see the working of LSA-4 and LSA-5 would be as follows:
Renumber the existing Area 25 to Area 0
Renumber the existing Area 0 to Area 2
Leave the existing Area 1 as is
Best regards,
Peter
10-16-2012 05:04 AM
Hi Peter ,
Its really very informative and satisfied with this answer ............
Discover and save your favorite ideas. Come back to expert answers, step-by-step guides, recent topics, and more.
New here? Get started with these tips. How to use Community New member guide