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# Calculating EIGRP Metric

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I have an ASA adjacent to a router with the following redistribution into the EIGRP AS shared with the Cisco ASA:

redistribute eigrp 100 metric 100000 0    255    1      1500 route-map EIGRP100-TO-EIGRP10

When I look on the ASA route table it's showing an AD of 170 and a metric of 25856 for the routes in EIGRP 10 that were redistributed from EIGRP 100.

EIGRP Metric = 256 * ( (K1*Bw) + ( (K2*Bw) / (256-Load) ) + (K3*Delay) ) * (K5 / (Reliability + K4) ) )    {I'm assuming default K values 1 0 1 0 0 }

K`1*BW            K2*Bw                    K3*dely    K5/Rel+K4

Anyhow the ASA is seeing traffic taking this route as 25856. I can not figure out where that number is coming from. The actual bandwidth between the ASA and router is 1Gbps.

Any insight appreciated!
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CERTIFIED EXPERT
Distinguished Expert 2018
Commented:
redistribute eigrp 100 metric 100000 0 255 1 1500 route-map EIGRP100-TO-EIGRP10
bandwidth = 100000, delay = 0, reliability = 255, loading = 1, and MTU = 1500.

Calculation is a little bit different. Actually bandwidth and delay are not in use per se, but scaled bandwidth and scaled delay.

EIGRP composite cost metric = 256*((K1*Scaled Bw) + (K2*Scaled Bw)/(256 – Load) + (K3*Scaled Delay)*(K5/(Reliability + K4)))

Scaled Bw = (10000000/minimum bandwidth (Bw) in kilobits per second)
Scaled Delay = (Delay/10)

When K = 0 values are removed from forumal, simplified formula looks like

EIGRP composite cost metric = 256*(Scaled Bw + Scaled Delay)

EIGRP composite cost metric = 256*(10000000/100000+0/10) = 256*(100+0) = ‭25,600

Since 0/10 will be rounded, I guess, that 0/10 will actually will be rounded to 1 which will match metric on ASA
256*(100+1) = 25856

Additionally, if wide metric is being used there metric rib-scale may be present and it will recalculate cost value before placing route in RIB.