EIGRP - Filtering neighbor?

[a.hed]

Hi

I have run in to a problem with EIGRP and redundant configuration.

We are about to migrate to a solution with existing hub and spoke routers but this time we will add redundancy at the central site.

The connection between the two central Hubs and the spoke router is one "bridge" or broadcast domain for each spoke router. and we will have about 400 spoke sites :-)

The problem is that the two Central Hub routers becomes neighbors on ALL interfaces.

I have configure delay on interfaces and an offset-list in the EIGRP process on central hub my tought was to have 50/50 loadbalansing between the hub routers.

If we look at the routing table it looks ok, but in the router eigrp topoligy it sucks big time.... every network have an alternate path on every interface.

Is there a nice way to fix this problem?

I have looked at the neighbour statement in eigrp but is it the solution for me? it seem to stop me from being able to route multicast?

Regards

///a.hed

[cadet alain]

Hi,

What exactly are  you trying to achieve ? You want some interfaces not to become neighbours?

Why don't you simply put these interfaces as passive?

The neighbour command is for configuring unicast hellos and stop multicast processing and sending on the interface you configure in the command so it could also work indeed.

Regards.

Alain.

[a.hed]

Hi

I want the spoke to be neighbor with the two central hub routers, but i do not want the hub to be neighbors on the same interface.....there is only one interface in the spoke and one interface in both the hub all 3 interfaces ( spoke and the two hub routers) share the same brodcast domain/L2 network. and I have 400 spokes with separate central interfaces This will cause the two hubs to become neighbours on all 400 interfaces. The two central routeres have a separate back-to-back connection and that is the only link i like them to be neighbours on.

It seem like the neighbour command is what i want.... but if it stops ordinary muticast routing i do not think this is an option for the future.

If I use the neighbour command do I need it on both ends... if i use it on the hub i must use it on the spoke?

regards

///A

[cadet alain]

Hi,

this command must be configured on both ends and it is configured under the EIGRP process specyfing which interface should use unicast for EIGRP neighbourship. If on same interface you want other routers to become multicast neighbour then the only solution I can think of right now is to use another EIGRP process for these neighbours and maybe do redistribution. Maybe someone more knowlegeable will find you another solution.

Regards.

Alain.

[a.hed]

Thanks for youre input

what If I configure different subnets on the central hub routers and configure secondary ip on the spoke what will happen? can this fake two different "links" in the same broadcastdomain?

///Anders

[Marwan ALshawi]

using this command got nothing to do with multicast routing such as PIM the multicast will use the unicast routing table to build the path/tree as long as the underlying network supported

this command only convert the EIGRP peering from being multicasted it will be unicast peering

hope this help

[cadet alain]

Hi,

No you'll have 2 different subnets not two different links and different subnets should be in different L2 broadcast domains.Furthermore if I remember well you can't do an EIGRP adjacency over secondary.

Regards.

Alain.

[Marwan ALshawi]

agree with Alain secondary IP won't work and will make it complicated for you

keep it simple !