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| 5.6 |  | Troubleshooting EIGRP |
| 5.6.1 |  | Mismatched K values |

For EIGRP to establish its neighbors, the K constant value to manipulate the EIGRP metric must be the same. In the EIGRP metric calculation, the default for the K value is set so that only the bandwidth and the delay of the interface are used to calculate the EIGRP metric. At times, the network administrator might want other interface values, such as load and reliability, to determine the EIGRP metric. Therefore, the K values must be changed. Because only bandwidth and delay are used in the calculations, the remaining K values are set to a value of 0 by default.

> Note: Cisco usually recommends that network administrators do not modify the default metric of using bandwidth and delay.

However, the K values must be the same for all the routers or EIGRP will not establish a neighbor relationship. An example of two routers with mismatched K values is illustrated.

Modifying the K values will affect how much, if any, of bandwidth, delay, reliability, and load will have on the metric calculation. Modifying these K values will have the following affect:

- K1 for bandwidth
- K2 for load
- K3 for delay
- K4 and K5 for reliability

Debugs and Verification
Figure shows the K values on RTR B have been changed to include load and reliability, along with bandwidth and delay. K1, K2, K3, and K4 have all been set to 1. The metric weights command shows that these values have been modified. The first value is the type of service (TOS) which is not supported, but must be included.

RTR A retains the default K values of K1 and K3 set to 1 for bandwidth and delay only, with all other K values set to 0. If router such as RTR A is using the default, normally the metric weights command would not be included in the configuration.

The command show ip eigrp neighbors on both RTR A and RTB B would show an empty list. Troubleshooting this problem requires careful scrutiny of the routers configuration.

Solution
The solution is to configure the same K values on all routers in the EIGRP domain. Figure shows the modification made to RTR A to match the K values on RTR B. At this point both routers will be able to establish a neighbor relationship and exchange routing information.