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1Mac to 2 Switchports


i want to connect a Server to my Switch. This Server has a NIC with 2 Ports. Both ports seem to have the same MAC Adress. The Server will send its traffic balanced over both Ports of its NIC which is connected to 2 Ports of my switch.

At the moment the switch is continuously reporting ".... %C4K_EBM-4-HOSTFLAPPING: Host 02:04:23:AC:50:A6 in vlan 10 is flapping between port Gi1/1 and port Gi1/2, rxload 1/255"

How will i have to configure the Switch that it's correctly forwarding the traffic from both ports without the Hostflapping message?

Is the first step to configure a channel for the 2 Switchports with load-balance?

How to solve the problem with the same MAC?

Thank you very much for helping me!


Re: 1Mac to 2 Switchports

HI Dbiedrma,

If both the nics connect on the same switch and you want both the nics to be active the best solution is to configure etherchannel between the server and the switch.

You have to configure teaming for your nics and configure etherchannel on the cisco switch and you can run LACP mode on the etherchannel.

To read more about etherchannel and LACP mode have a look at this link