# redistributing different AS

Aug 12th, 2007

dear all,

i have this nice discussion which is not really solved yet.

between 2 routers : can we redistribute 2 different EIGRP AS? said RA EIGRP 100, RB EIGRP 101?

some folks showed me docs from cisco - which is we have to use 3 routers with on on the middle having 2 AS --> said RA EIGRP 100, RB EIGRP 100+101, RC EIGRP 101.

And, my answer was sure we can have 2 routers but with 3 AS --> said RA with EIGRP 100 & 102, RB with 102 & 103.

i mean what is the difference between them, and which one proofed to be better solution?

any idea would be appreciated. thank you.

regards,

Intelide3

> can we redistribute 2 different EIGRP AS? said RA EIGRP 100, RB EIGRP 101?

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Yes. You will need a common AS for them to form adjacency, said AS102 per your example, and then perform mutual redistribution.

On RA's EIGRP processes, you will redistribute AS100 under the AS102 process and vice-versa. Same procedure is done in RB with AS102 and AS103.

HTH,

Overall Rating: 5 (1 ratings)

## Replies

Edison Ortiz Sun, 08/12/2007 - 07:10

> can we redistribute 2 different EIGRP AS? said RA EIGRP 100, RB EIGRP 101?

___________________________

Yes. You will need a common AS for them to form adjacency, said AS102 per your example, and then perform mutual redistribution.

On RA's EIGRP processes, you will redistribute AS100 under the AS102 process and vice-versa. Same procedure is done in RB with AS102 and AS103.

HTH,

intelide3 Sun, 08/12/2007 - 07:30

thank you very much Mr. Ortiz,

its nice to have a clear answer from an IE :)

thank you.

clintplotts Sun, 08/12/2007 - 10:20

So does the method you choose depend on the number of routers you have that will perform redistribution?

I see in this example the 2 different methods call for 2 routers or 3 routers. IN the real world, which method would be more used?

Edison Ortiz Sun, 08/12/2007 - 11:00

The method you choose depends on what you need to accomplish. If you need to have multiple EIGRP ASes in your environment, you need to determine where to place the point of redistributions and what routes to allow/deny between ASes.

Actually, that's the main goal for having multiple ASes, that is granular management of the EIGRP topology within your network.