The remote mirroring feature copies select traffic from select ports and VLANs and sends the copied traffic to a remote switch for analysis.
The mirrored traffic is sent using a VLAN that is configured for this purpose. For more information, see MLAG Limitations and Requirements.
Transit switches are the switches between the source switch where ports are mirrored and the destination switch where the mirrored traffic exits the network to a network analyzer or network storage device.
Because the mirrored traffic is an exact copy of the real traffic, a transit switch can learn the MAC addresses and make incorrect forwarding decisions.