Admin Tool Radius is a powerful tool developed by and intended for system administrators who require Radius settings on OS X Server. This tool has been tested from Mountain Lion up to Yosemite.
Admin Tool Radius allows you to enable the OS X Server's built-in Radius service to use your server as an AAA server for any kind of Network Access Server (VPN concentrators, Wireless Access Points, etc.).
Admin Tool Radius will also allow you to monitor your server by providing access to logs files.
To be able to use this tool, you'll need to enable remote administration via Server.app. This tool uses the same protocol.
A simple howto has been written by one of our users, it can be read here http://servicemax.com.au/tips/admin-tool-radius/
If you have some problems with the app, you can contact the developer directly at firstname.lastname@example.org (in english or french). By talking directly I can help you and fix any eventual bugs.
Note: This tools is only intended for system administrators who manage OS X Server. You are supposed to know what you are doing. The developer of this application can't be held responsible for inappropriate usage of this tool. This tool does not add capabilities to the server, it just allows you to configure hidden settings. This tools does not fix server bugs. OS X Server’s built-in radius server is freeradius.