Hi WW & Brash,   Thank you for your reply. I have found the cause of issue is the wireless controller firewall rule.  ... View more

Make sure traffic analytics is set to detail. https://documentation.meraki.com/MR/Monitoring_and_Reporting/Hostname_Visibility    You could go to Network Wide/Clients, change to looking at the last 2 hours, and then sort the table by data volume.  Whatever is at the top is most likely to be the issue. ... View more

Hi,   Thanks for your reply. I got it. ... View more