Recently I got a case for Agile Controller related to portal authentication. Customer allow Windows to install the latest patches to the operating system and it had to restart it. After this event the users were unable to perform portal authentication and the error message received was this one:
Lets troubleshoot this problem.
1. Since the server was restarted we will try to see if all services started properly, how to check this:
Into Start/Run field type Services.msc, in the new window check the services status associated to Agile Controller
2. All the services were in "Started" state, we will need to look into different direction. Since the error was related to authentication, "login failed" I decide to check the radius connection by trying to search the process id associated to radius. Check below output, port 1812 is associated to radius protocol and the proccess id match with radius server application.
3. Since the Radius connectivity is working, it will be useful to check the error received on radius server matching the "login fail" mesage. In our case, the error message was "Identify authentication failed".
4. Based on the error message received, we should check the authentication and authorization rule action, if it's permit or deny. In our situation the action is permit.
In our case the port was occupied by another process, dns.exe, for some reason after reboot DNS service occupied this port number. We kill the proccess temporary and portal server start on the 50100. This is how the port status and application information should look normally.