The Meraki dashboard has NEVER shown devices or OS's accurately.
Meraki APs identify clients using a technique called OS fingerprinting. Each OS, and sometimes version of an OS, has a unique DHCP fingerprint. By examining a client’s DHCP request, we can tell which OS it is running.
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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