Errors

If the server does not start, it prints a descriptive message to the log files, or to the terminal window. The common errors are listed below.

When the server successfully starts in debugging mode, the last line it prints is:

When it receives packets, it either prints out an error (as discussed in the next section), or it processes the packet through the unlang policies. However, sometimes it just prints out Ready to process requests, and then nothing happens. i.e. it doesn’t print out any messages. So what’s wrong?

The problem is simple: the server isn’t receiving any packets. If the server receives a packet in debug mode, it always prints out a message, without exception.

So if there are no messages being printed, that means the server isn’t receiving packets. There are a number of reasons why this happens. Perhaps the client isn’t sending packets. Perhaps the packets from the client aren’t reaching the machine which is hosting the server. Perhaps the OS has a firewall, and is dropping packets before they are sent to the server. Or maybe the OS is discarding packets for another reason.

The root cause of the problem can only be determined by eliminating each of the above possibilities. You can’t fix the problem simply by asking "we sent packets to the server and it didn’t receive them, so what’s wrong with the server?". The only possible answer to that question is "nothing". The problem isn’t in the server, it’s elsewhere. Things you should check include:

All of these should be checked beforing checking any FreeRADIUS configuration.

When the server discards packets for a particular reason, it gives a descriptive error messages when running in debug mode. The errors are not sent to the normal log file, because that could allow attackers to DoS the server.

The common reasons why packets are discarded are listed below. When run in debugging mode, the server also prints out a reference to the specific page that is associated with that error.