In the Meraki dashboard, we can whitelist 3000 wireless clients. Is it for the entire network or for the specific SSID?
It's by network
What will happen if we whitelist more than 3000?
Just filtering the clients to which it is applied, there is no counter.
Where do we see the whitelisted client count details in the dashboard?
On the clients page. https://documentation.meraki.com/General_Administration/Monitoring_and_Reporting/Client_Details_Page...
If we whitelist one of the device's MAC, how many days will it exist in the dashboard? If we can't connect the whitelisted device to the wireless network for more than a month, will it exist, or can we connect the device after 50 days from the day of whitelisting?
Take a look at the cloud data retetion policies
https://documentation.meraki.com/General_Administration/Privacy_and_Security/Cloud_Data_Retention_Po...
If the whitelisted working device gets inactive for 3 months, will it work after 3 months?
Yes
Some of the wireless clients frequently disconnect from the network. How can we mitigate that?
You need to be more specific, in this case I suggest you open a support case.
Is there any way to see all the client's individual connectivity time on a single page with the graphical representation for the specific SSID?
On client details. https://documentation.meraki.com/General_Administration/Cross-Platform_Content/Clients_Usage_Page_Ov...
For each of your questions you can read the documentation or open a support case.
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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