We have a MX100 (firmware 13.28) and it is connected with our Active Directory. Everything is working fine in this regards but since a few weeks we lost the ability to see who is connected on client in client view. On some rare instance we still see it but for the most part we lost this feature. Anyone can help me with this?
Have you went to Security Appliance>Active Directory and double checked that the status is still a green check. It'd be a good place to start to make sure that, for some reason, the account it is using etc didn't get borked.
Two more things to check.
Go to Network Wide>General and check the 'Traffic analysis' section and make sure it is set to 'Detailed: collect destination hostnames'
Also worth taking a look at Security Appliance>Addressing & Vlans and check the 'Client tracking' section. Here is some info on that section https://documentation.meraki.com/MX-Z/Monitoring_and_Reporting/Client_Tracking_Options