Perfect, you need to install AD CS.
RADIUS Server Requirements
There are many server options available for RADIUS, which should work with MR access points if configured correctly. Please refer to your RADIUS server documentation for specifics, but the key requirements for WPA2-Enterprise with Meraki are as follows:
- The server must host a certificate from a Certificate Authority (CA) trusted by clients on the network.
- All gateway APs broadcasting the WPA2-Enterprise SSID must be configured as RADIUS clients/authenticators on the server, with a shared secret.
- The RADIUS server must have a user base to authenticate against.
Once the RADIUS server is configured, refer to the Dashboard Configuration section below for instructions on how to add your RADIUS server to Dashboard.
https://documentation.meraki.com/MR/Encryption_and_Authentication/Configuring_RADIUS_Authentication_...
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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