Strange EIGRP Behavior

[PolyCaleb]

So I have a situation where I have a layer 3 switch (R3-1) that is 2 hops away from the subnet on R1 (another layer 3 switch).  It has formed an eigrp neighbor with the two layer 3 switches (R2-1 and R2-2) that are one hop away from R1 however it is not getting the route to R1 but instead it is getting a route that goes through R4 which is connected to R3-2 (which then connects back to R2-1 and R2-2).

All ports are gigabit Ethernet ports (so they have the same cost) and every layer 3 device has router eigrp 100.

I've attached a network diagram with direction the route is passed and what the composite metric of the route is (from show ip eigrp topology 10.1.1.16/28 on each device).

How do I get R3-1 to be the proper 2 Hops from R1?

[Georg Pauwen]

Hello,

post the output of 'show ip eigrp topology' from Router R3-1.

Is this a live network or a simulation ?

[PolyCaleb]

So this is a live network, which makes me leery of posting the complete "show ip eigrp topology".  Is there something in particular you are looking for?

[Georg Pauwen]

Hello,

the thing is, even with advanced traffic engineering it is pretty hard to get a route over 4 hops preferred to a route over 2 hops.

Check the configs of the routers and if things like the delay on the interfaces have been altered...

[PolyCaleb · Accepted solution]

So going through the show ip topology I found that only the subnets on R1 were misrouted.  R3-1 has the appropriate number of hops to subnets on other switches that were similarly connected as R1.

When I looked I found that the Router ID was the same on R1 as it was on R3-1.  I fixed the Router ID to be different and it resolved the issue.