MAC conflict: A port on the virtual switch has the same MAC as one of the underlying team members on

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MAC conflict: A port on the virtual switch has the same MAC as one of the underlying team members on Team Nic Microsoft Network Adapter Multiplexor Driver.

 

how to fix this issue ? 

2 Replies

the layer 2 part of the TCP/IP stack runs according to MAC address before even IP addresses are taken into account at layer 3. The ports are designed to work by the traffic being switched according to MAC address and the ARP. If the member ports of a team are different from the MAC address of that interface then traffic will fail to route through. The VM host and VMs aboard run by the same rules, so although this comes up as an error, it is part of the way that route 2 traffic is routed. You can change the MACs in device manager under the properties of the NIC and the Address Resolution Protocol will relearn the routes but this error sounds quite worrying when in fact it is perfectly natural.

See here: mac conflict a port on the virtual switch has the same mac as one of the underlying team members on