Hi all,
It is known that normal/basic EIGRP calculation = (minimum bandwidth + (sum of all delay)) * 256
Let's say there a 2 hops from source A to destination B
A --bw1--> [R1] --bw2--> [R2] --bw3--> B
q1) why does it only use the minimum bandwidth ? Wouldn't it be more accurate to calculate the individual bandwidth between hops ?
For example, the above exhibit, R3 FD to network 5.0 is using the R4'sRD + (R3's Delay/10 * 256) only which is 28160 + (10*256) = 30720
Why isn't the calculation = (R3 metric to R4) + (R4 metric to 192.168.5.0/24 network) = 28160 + 28160 instead ?
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MTU 1500 bytes, BW 10 Kbit, DLY 100 usec,
reliability 255/255, txload 1/255, rxload 1/255
Encapsulation ARPA, loopback not set
ARP type: ARPA, ARP Timeout 04:00:00,
Last input 00:00:08, output 00:00:05, output hang never
Last clearing of "show interface" counters never
Input queue: 0/75/0 (size/max/drops); Total output drops: 0
Queueing strategy: fifo
Output queue :0/40 (size/max)
5 minute input rate 6877 bits/sec, 6 packets/sec
5 minute output rate 117 bits/sec, 3 packets/sec
q2) Above is using packet tracer, i am not sure if it is a bug or my calculation is wrong.
I have understood rxload = (input rate/1000/bandwidth) * 255
= 6.877/10 * 255
= 175/255
But i keep getting 1/255 ..
q3) Also, i am doing a ping out to another destination, why is my input rate higher then my output ?!
Is input = incoming traffic ? Did i misunderstood the meaning of input rate ?
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q4) It is mentioned in many places that to get the overall bandwidth utilization of the link in percentage, you cannot add both the txload+rxload/255 * 100 - is this because the value reflected in txload or rxload is calculated base on a single direction bandwidth in a full duplex connection ?
q5) how is reliability calculated ? 255/255 ? I googled around but can't find an exact answer..
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Hope gurus here can shed some light.
Thank you!
Regards,
Alan
