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Unicast traffic seen on host port that is not for the host.

We have two Nexus 5k's connected to 8 fex's in a dual homed vpc topology.

We are seeing from a span session unicast conversation traffic on the host fex port that is only one way, and from two hosts that are not on that fex port. We just upgraded to 5.0.3(N1).n1c about 90 days ago and our server guys are seeing numerous other conversations on their port when running tcp dump. Has anyone experienced this? The perception is that this is what is causing the users application to be slow. There are no logs showing errors, there is not any detriment on the bandwidth. However disproving this is going to be a bit of a challenge. This port should not see this traffic.

Any bugs that i missed on this? Thanks in advance.


Unicast traffic seen on host port that is not for the host.

Is the destination mac address already present in the global mac address table ?

Could you see the same behavior through the installation of a sniffer on the server instead of using a span session ?

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