Expert Redistribution

I created this lab based on the INE article from Petr Lapukhov about redistribution. I recreated the lab only the IP addresses are different. If you are studying for CCIE this is an excellent lab, even if you are studying for CCNP and want to know exactly how redistribution works this is an excellent lab.

If you have trouble make sure to read Petr's articles:

http://blog.ine.com/2008/02/09/understanding-redistribution-part-i/
http://blog.ine.com/2008/02/19/understanding-redistribution-part-ii/
http://blog.ine.com/2008/03/17/understanding-redistribution-part-iii/

Hi William,

I recreated this lab but used my own IP addressing scheme. Which task is not clear? Where you have to make sure you need to use the FastEthernet links instead of the Frame-Relay?

Once you start redistribution you might have some ineffective routing where you don't have the shortest path. That's something to take care off and fix.

Thanks for the great lab and that article. But the IP in that article is different and it's not clear enough. This makes the answer to the last part of this lab difficult to understand.

after i remove the network 1.0.0.0 from router baby doll routers sweetpea and rocket don't remove the network from their routing table.
does it make any sense?

Avi Harari
this is what is meeans
Babydoll
no net 1.0.0.0
redistribute connect

This should work.

What a great lab! Was a little confused on how EIGRP356 was to see the 1.1.1.0/24 as there was no mention of redistributing between the EIGRP domains in te lab requirements. So I then read the articles by Petr Lapukhov. Learned way more than I expected! Definitely worth the time!

In order to achieve full connectivity on every device I had to redistribute EIGRP process 123 and 356 into each other on Router 3 (Rocket), otherwise Router 6 (BlueJones) doesn't have a route to Router 1 (BabyDoll. I suppose this is because a local route can't redistributed back into itself (On Router 3 EIGRP123->OSPF243->EIGRP356) or is there a better explanation?. Perhaps you should add that step to the instructions? Unless I was missing something...

@Rob I really like the articles that Petr wrote since it combines everything you need about redistribution on CCIE level. For CCNP it's a bit overkill but for anyone that wants to know the ins and outs of redistribution this is awesome.

@Barry You found the correct solution and your explanation is correct. I'm not sure if i'll add it as a task. Without the task you had to think a bit and you'll never forget that two-way redistribution isn't going to work ;D If i add the task then people will just hammer in the commands without knowing why or how. If I record the video then i'll show it for sure...good job!

dear:

kindly add video solution for this lab

@Barry / Rene - Are you sure about that ? As I see it R3 receives the 1.1.1.0 route via OSPF BUT it's not added to the routing table as the same route is recieved via EIGRP (with a lower AD). As redistribution from OSPF to EIGRP on R3 only redistributes OSPF found in the _routing table_ it doesn't matter that it actually has an OSPF route for the subnet.

A solution could probably be to modify the administrative distance for EIGRP routes on R3 ?

I'll see if I can record this one this week. It's a tough lab and it'll take some time...I'll see if you are right then Uffe

excellent lab. Just want to ask a few things.

1. In the INE setup they use ACLs to match subnets for split horizon. I've used tags to do the same thing. No issues with that?
2. To achieve the final requirement to use Fast Ethernets, I've just played with administrative distances. On R4 I said OSPF external is higher than RIP, on R5 I've said RIP is higher than EIGRP external. and this way R4 tries to use R5, unless R5 redistribution fails.

Hi Bal Birdy,

I'm not entirely sure, I'll answer your question once I've recorded the lab ;D

Rene

With complex topologies like this, there are always multiple solutions.

The biggest issue is R6 not learning a route to 1.1.1.1.
Just like anybody else who posted here, I was not able to find a workaround other than to start redistributing between AS123 and AS356. This creates a best path via R3. However, there is a backup path from R6 to R1 via R5-R4 through the ospf domain. R6 will use this path after configuring a default route to Null0 on R5 which is redistributed in AS356.

Probably I have been cheating a bit by incorporating all ethernet links on the path R2-R3-R5-R4 into ospf area0. ;D However, this is the superior solution when you want to ensure redundancy AND optimal path selection among these routers. Also, R5 is not redistributing any protocols.
The other magic command is distance ospf external 180.

Another thing to note is that we have to set the rip default-metric 1. IMHO this is a bug which I have encountered in other IOS versions as well.
All in all, the solution I worked out operates without any conditional redistribution or distance/metric setting via route maps.

regards,
Leo

I thought I was gonna go crazy trying to get R6 to see EIGRP 123 routes, until I read these comments.

I learned so much hunting for answers. I didn't want to just "cheat" and redistribute 123 and 356 into each other on R3