If you are not using an SM, on dashboard alerts, you can check this information:
- Clients connect or disconnect from the LAN
Sends an email if select clients connect or disconnect from the LAN, as observed by the MX. The MX sends an ARP request to the client approximately every ten seconds to monitor its connectivity status. If the MX does not receive an ARP reply from the client after approximately 35 seconds, it considers the client to be disconnected. Once the client begins sending data through the MX and responding to ARP requests, it will again be marked as connected.
https://documentation.meraki.com/General_Administration/Cross-Platform_Content/Alerts_and_Notificati...
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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