EIGRP deny in local lan broadcast network

[Binu Steephen]

I have three eigrp configured routers A, B , C in a single broad cast LAN.I want to deny router A eigrp peering with router B, need to retain A peering with C. what is the best solution.

A router

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no neighbor <B router lan ip> under router eigrp   will work ?

or

how can i deny using the multicase ip address 224.0.0.10 usinng access lis an din which direction i need to apply.

[cadet alain]

Hi,

on RTR A : under eigrp process  type neighbour "ip of RTR C" "LAN interface" command

on RTR C: do the same

Then these 2 routers will form an adjacency using unicast and RTR A won't accept multicast hellos from RTR B and so wont form an adjacency with it.

Regards.

Alain.

[Binu Steephen]

"deny eigrp any any" on LAN interafce of A and C we need apply with access list inbound, corrcet?

option II

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is this ok if we apply "deny eigrp host "C IP" to host A  IP" using inbound ACL on router A lan interafce and respective on C router as well.

Please advise.

[Amit Aneja]

A & C need to form EIGRP peering, A doesn't want to peer with B:

Two options:

1) Use unicast EIGRP hellos on A & C by using neighbor statement on both of them.

On A:

router eigrp 100

neighbor

On C:

router eigrp 100

neighbor

2) If you want to use multicast hellos, just tse "deny eigrp any any" in inbound direction on B, so that the hellos coming from A or C are dropped. By doing this, B won't be able to peer with anyone on that LAN interface.

HTH,

Amit

[cadet alain]

if you want RTR B not to be adjacent with the other 2 routers you can do as I proposed above that is enable unicast hellos on RTR A and RTR C.this way as RTR B is still doing multicast its hellos will be dropped on the 2 other routers which only accept unicast hellos and as it is only listening to multicast hellos it will drop the unicast ones from the other 2.

You could also leave multicast everywhere and filter eigrp packets from Router B inbound with an access-list like you proposed applied on RTR A and C interfaces.

Or like Amit said filter inbound on RTR B eigrp hellos from A and C.

Regards.

Alain.