Eigrp As

[caijunjie]

Hi

I would like to know if it is ok to have configure more than 1 eigrp as on a single interface in a same router. Example would be as below

router eigrp 10

network 10.10.10.2 0.0.0.0

router eigrp 20

network 10.10.10.2 0.0.0.0

Will there be any issue for the above although I know the router allow me to do that.

Hope someone can advice.

Alan

[francisco_1]

you can advertise the 10.10.10.0 network under different eigrp AS number (advertised via different interface) on the same router if the 10.10.10.0 is in the routing table or is directly connected interface on the router

[Giuseppe Larosa]

Hello alan,

you can do it, because eigrp AS is present in the hello and other eigrp packet types.

So on a physical interface (or VLan subif) you can have 0 or more eigrp neighbor(s) for each of the two EIGRP AS numbers.

you can use sh ip eigrp neigh

sh ip eigrp topology and so on to filter output.

Be aware that without redistribution you will have a ships in the night scenario where the two eigrp domains are separated and don't share information and have separate topology DBs.

Hope to help

Giuseppe

[caijunjie]

thanks for all the reply. Actually I got this from a lab. The lab is preconfigured to have eigrp as 1 on all the interface but thee a task to call me to configure another eigrp AS on the same interface. I am able to do that without any issue.

Question, may i know in a real production network, under which situation would we want to do this ? :)

Hope everyone understand my ques.