verify multicast flow timer and RTO in EIGRP
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01-14-2023 12:14 AM - edited 01-16-2023 06:19 AM
Hello
Thanks for your time to help.
I am learning EIGRP. May I have your help?
In Reliable Transport protocol (RTP), after device send packet to 224.0.0.10, it will wait a time call multicast flow timer. This default is 50, unit is second.
If not receive ACK, it will send unicast, the interval would be Retransmission Timeout (RTO). This default is 100, unit is ms. 100ms = 0.1s
I use below network to verify. I don't know why R1 Multicast Flow Timer become so large. Now I will shutdown R1 e0/1 and then shutdown R3 loopback0 immediately. I suppose this will trigger reliable multicast.
My question is
Q1. Time between first multicast and first unicast, the interval is 94.506468-94.406707=0.099761s. This not match Multicast flow Timer 50s.
Q2. R3 will remove R1 after 3 times of Hello, which 15s. Device send unicast query after neighbor already removed? this not make sense.
Thank you.
Best Regards.
Scott Gao
Below is initial status
I don't know why R1 Multicast Flow Timer become so large. Now I will shutdown R1 e0/1 and then shutdown R3 loopback0 immediately. I suppose this will triger
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01-14-2023 04:14 AM
Hello,
post the full running configurations of all three routers as well as the exact command sequence you are executing, so we can lab this up.
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01-15-2023 03:34 AM
Dear Georg
I had edited post. Please check is it enough.
Thank you.
Best Regards.
Scott Gao

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01-14-2023 04:14 AM
Hello,
post the full running configurations of all three routers as well as the exact command sequence you are executing, so we can lab this up.
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01-16-2023 05:40 AM - edited 01-16-2023 05:41 AM
Dear Georg
I edited again my post. Could you please check? Attachment include whole PNETLab config and all devices configuration. On the other hand, I post configuration by screen capture.
As a background, I had not understand SRTT.
Does information enough?
Thank you.
Best Regards.
Scott Gao
