Multiple autonomous system in eigrp.

If I configure more than one EIGRP autonomous system on the same router then will they communicate/exchange routing info with each other if not then how to do so ?

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Comments

killuah72

No they won't be able to communicate with each other because they are in different autonomous systems. If you want them to share networks then you can use redistribution.

billscott92787

killuah72 wrote: »

No they won't be able to communicate with each other because they are in different autonomous systems. If you want them to share networks then you can use redistribution.

As killuah said they will not share information unless you redistribute the routes from each different instances of EIGRP. You could have several different instances of different AS's running on the router, and they do not necessarily have to be reditributed. But, without using redistribution, the AS numbers have to match. So if one router has AS1 and the other router has AS1 then they will exchange information, as long as they both have a matching network statement, which links them to being on the "same subnet." Example

R1
router eigrp 1
network 10.1.1.0
no auto-summary

R2
router eigrp 1
network 10.1.1.0
no auto-summary

Now these routers could also include network statements to other networks say R1 has a loopback of 1.1.1.0, if it adds that to its' network statement, then that route will be advertised to R2. But when your dealing with different autonomous systems, the only way is redistribution.