The recentDeviceMac field does not necessarily guarantee that the client is directly connected via Ethernet to that specific switch. There are scenarios where the client could be connected through an intermediate device, such as a downstream switch, a hub, a docking station with built-in networking.
In these cases, the recentDeviceMac would still show the MAC address of the Meraki switch that the intermediate device is connected to, not the intermediate device itself. Therefore, it is possible that there is an "intermediate" switch or device between the client and the Meraki switch.
To reliably determine if a client is directly connected via a wired connection, you may need to cross-reference additional information, such as the port status and the MAC address table of the switch. This can help you identify if the client's MAC address is directly associated with a specific port on the switch or if it is being learned through another device.
I am not a Cisco Meraki employee. My suggestions are based on documentation of Meraki best practices and day-to-day experience.
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