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New Member

EIGRP Metric Manipulation issue

Hi,

I have a question about how to influence the routes learned from a specific EIGRP neighbour. 

We have one multi-access vlan with 2 core switches and 2 routers. Switch A and Switch B have the same routes (shared VLANs). Router A and Router B have also the same routes, but different networks.

Router A and Switch A should have default EIGRP settings but routes learned from Router B or Switch B should be less attractive (influenced).

I am stuck how to do this.I have tried looking at distance, distribute-lists and route-maps but cannot get an EIGRP only solution to make this work.
Can anybody give me some pointers how to solve this?

Kind Regards, G.

9 REPLIES
New Member

Hi ,  I think you might

Hi , 

 I think you might change the interface bandwidth connected to router B , and make it lower than BW connected to switch A , this should trigger the EIGRP metric and prefer the switch A side, instead of Router B or SW B.

Bandwidth interface won't affect your Original BW.

> I think also apply Route-map on the interfaces connected to SWB , Router B that increase the metric learned by those interfaces which will make these routes less attractive. 

hope this will help.

Regards, Mahdy :)

New Member

All the problem is that the

All the problem is that the setup is that both Switch A and B are in the same VLAN connecting to routers A + B.

EIGRP-IPv4 Neighbors for AS(10)
H   Address                 Interface              Hold Uptime   SRTT   RTO  Q  Seq
                                                   (sec)         (ms)       Cnt Num
2   11.254.8.28 (RTRA)            Gi0/2/0                  13 1d11h       5   100  0  523699
1   11.254.8.17 (SWB)             Gi0/2/0                  12 1d11h      12   100  0  1237961
0   11.254.8.1 (SWA)              Gi0/2/0                  11 1d11h      14   100  0  1314074

So modifying the delay would have the same result as for router A, Switch A and Switch B. Thus not differentiating between RTRA+SWA vs SWB.

HelloEigrp delay is

Hello

Eigrp delay is calculated with all the interfaces delay in the eigrp path, so this means you can manipulate an upstream rtr on the B network to provide a less proffered  route if this is applicable to your toplology

res

Paul

Please don't forget to rate any posts that have been helpful. Thanks.

As mentioned by Kwillacey,

As mentioned by Kwillacey, Use the offset list to change the composite metric on the link between your neighbors, you can follow the direction on the following page to configure :

http://www.cisco.com/c/en/us/support/docs/ip/enhanced-interior-gateway-routing-protocol-eigrp/13673-14.html#modifycompositemetric

Look at the direction the Offset-list is applied for expected results.

Manish

New Member

you can useACL's and offset

you can useACL's and offset-list to increase one metric going in or out of an interface. 

so

access-list 1 permit 11.254.8.17 0.0.0.0

router eigrp 1

offset-list 1 in 5000 Gi0/2/0

 

What that does is in the topo table increases the EIGRP metric for 11.254.8.17  inbound on gi0/2/0 on RTR-A. 

 

You might need to switch the logic to get the result that you want, but that is the commands that can get it done for you. 

 

Good luck

 

The rule of thumb is to use

The rule of thumb is to use delay not bandwidth to influence path selection. You can also try an offset list but modifying the delay should be sufficient.

New Member

you are right K (Y) , i

you are right K (Y) , i missed this point 

HelloThe best way is to

Hello

The best way is to increase the delay value on the handoff interface of the B network as this will make the A network more preferable..

something like this:

int xx

delay 20000

 

res

Paul

Please don't forget to rate any posts that have been helpful. Thanks.

Can you post a diagram?

Can you post a diagram?

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