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Webcast-Catalyst9k
New Member

layer 2 issue

I have a frame with dest mac A getting to gateway which has a mac of B. How is that possible. Mac A is the mac of a device present on LAN. Question is how does the frame get to gateway using a different dest mac than the gateway's mac.

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It's a unicast MAC?  If so, could it have been unicast flooded?  Or, SPAN isn't configured, is it?

New Member

It is Unicast. No SPAN

It is Unicast. No SPAN configured. Plenty of mac room and also all macs involved are correctly in mac table of the switch (N6k) with corresponding interfaces. IG bit and LG bit both 0. What else can I check ?

Silver

Is MAC A a directly connected

Is MAC A a directly connected device to the same switch? If no, what is the topology?

New Member

Could it be that there is a

Could it be that there is a standby ip configured, at example HSRP or VRRP protocol?

In this case the destination MAC to the Gateway would be a virtual MAC of the protocol and not the Interface MAC of the Gateway. 

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