EIGRP metric

As we know, K1 and K3 are set to a value of 1 by default, and other values are set to 0. Armed with that information, we can reduce our formula to the following:

EIGRP Metric = 256*(10000000/Bw + Delay)

Bw in kilobits, delay in tens of microseconds

Note the Bw is the MINIMUM bandwidth from point A to point B. For a packet from R1 to R10, R3 s1/0 interface and R10 f0/0 interface use the same Bw value which is R3 s1/0 bandwidth to calculate their own metric. So for a given path, when calculate each metric on each router inbound interface, the metric difference is the difference of Delay portion. For example, the difference between R10 f0/0 metric and R3 s1/0 metric is

Metric Difference =  256 * (R10-cumulated-delay - R3 cumulated-delay)

for the neighbor router like R10 and R3, the increased metric on R10 f0/0 interface is 256x local interface Delay calculated value.

So R10 f0/0 interface metric = R3 reported metric + R10 f0/0 local delay calculated value. In case of F0/0 interface delay is 100 usec:

R10 f0/0 interface metric  = R3 reported metric + 256*10