Tagged Redistribution Help (ROUTING)

Hi all,

Just need some input here..

I understand the concept quite clearly - Traffic (packets) are tagged and with route-map and redistribution they are then stopped from being re-redistributed from a secondary router (full redistribution of 2 IGPs).

I have been playing with a lab, and either the lab is broken, or something I am doing is wrong. Here is the scenario::

(R1)Rip to (R2)Eigrp full redistribution. (R3) is in RIP, (R4) is in Eigrp.

After enabling full redistribution - a routing loop will occur as routes learned from R3 are distributed into the Eigrp domain, then advertised into RIP as eigrp traffic (from R3). Common error. One way of fixing it is by using a Route-map and tagging the traffic.

route-map rip-to-eigrp deny 10
match tag 1

route-map rip-to-eigrp permit 20
set tag 2

route-map eigrp-to-rip deny 10
match tag 2

route-map eigrp-to-rip permit 20
set tag 1

EIGRP AS > redistribute rip route-map rip-to-eigrp metric 1 1 1 1 1

RIP > redistribute eigrp (AS#) route-map eigrp-to-rip metric 6

If I understand this correctly :
traffic redistributed from rip into eigrp is tagged with (2) & permitted to enter & changed to eigrp traffic //
traffic redistributed from eigrp into rip is tagged with (1) & permitted to enter & changed to rip trafic //

Also, traffic that is then re-redistributed (looping) carries certain tags - those tags are denied/stopped/blocked --
ex -- rip is redistributed into eigrp - these routes are advertised to the rip domain - at this point it is blocked due to the tag (2) blocked by the route-map (eigrp-to-rip) that says that traffic tagged with tag (2) should be blocked. and vice~versa.

In my lab I am still getting loops and it seems that the redistribution is not working the way I think it should.

From the above - is there a problem ?

appreciate any help.

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Comments

Dieg0M

Are you applying the route-maps on both redistributing routers?

networker050184

chowzen wrote: »

I understand the concept quite clearly - Traffic (packets) are tagged and with route-map and redistribution they are then stopped from being re-redistributed from a secondary router (full redistribution of 2 IGPs).

No you aren't understanding it quite clearly. Traffic is not tagged. You are confusing control and forwarding plane functions.

Dieg0M

Read this Redistribution loops and please tell me what kind of redistribution loop you are getting and provide a 5 min debug ip routing output.

chowzen

Hey. Thanks for the replies..

Please see my reply below. In order to make things alot easier, this is the lab I am referring to : RIP EIGRP Redistribution Route Tagging

I am issuing the route-map as shown above and adding it to my redistribution command. The moment I do this, all the advertised routes disappear from one router (I assume it is the cannot advertise what you do not know rule) and the other router stays the same (this happens when I issue the redistribution w/route-map from both routers).

I would be grateful for any advise or recommendation.

phoeneous
Yes - I will post link to it. I simplified the question to the Lab.

Dieg0M
Yup.
Secondly, I did not save the lab that I performed. So it is back to its default as released by René.

networker050184
Clearly I am not. The idea of incoming and outgoing traffic makes sense, but I am struggling to get into my head the flow and rules around tagging traffic being fully-redistributed.

networker050184

Traffic isn't being tagged, the traffic really has nothing to do with it. Routing updates are tagged which the routing processes take action on. As traffic is forwarded it is not part of a certain routing protocol and tagged as such.