Multi Copies of same frame

Unanswered Question
Oct 13th, 2007

STP/RSTP does not handle multiple copies of the same frame from different ports on the same switch/vlan. Is there another protocol that handle this situation without corrupting the mac table?

I have this problem too.
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Kevin Dorrell Sat, 10/13/2007 - 17:21

Multiple copies of the same frame from different ports on the same switch will not "corrupt the MAC table" as such, but is known as "host flapping". If STP/RSTP is doing its job correctly, then it simply should not happen, and can be regarded as a breakdown in you network topology.

Do you have a specific problem you would like to tell us about?

Kevin Dorrell


crem_cisco Sat, 10/13/2007 - 19:54

A vendor provided five servers with the same MAC software defined. They worked fine until I moved them to the same lan segment. Using wireshark, I seen what appears to be copies of MAC going into the switch. "show mac-address-table" had incomplete statements. This put the switch (C2950G) utility to 90%. STP/RSTP does not appear to be able to handle this situation well. Is there another layer 2 routing protocol that would handle this scenario better?




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