Client-related problems

A user connects to a RADIUS client; the RADIUS client in turn connects to the RADIUS server. If a client does not seem to be able to connect with the server check the following first:

• Does FreeRADIUS knows about this client? Check the FreeRADIUS log file for lines like the following:

  Wed May 18 17:53:57 2012 : Error: Ignoring request to authentication address * port 1812 from unknown client 192.168.1.103 port 39881
  

• Is the client allowed through the firewall running on the FreeRADIUS server? To check the firewall rules use the following command (requires root access):

  #> /sbin/iptables -L -n
  

If these initial checks have passed, run FreeRADIUS in debug mode in order to do proper troubleshooting. The debug messages will show when a request is received and how it is processed. These debug messages are verbose, containing lots of detail making it easy to follow.

Unfortunately, when you run FreeRADIUS in a production environment it is not always easy to first stop the FreeRADIUS...