Time for action – investigating the default realms in FreeRADIUS

In the following exercises we will learn about various aspects of realms. We will start with a clean installation of FreeRADIUS and change it subsequently to see how it handles various realm configurations:

Tip

Ensure you have a default installation of a FreeRADIUS server.

1. Edit the users file located under the FreeRADIUS configuration directory and make sure the following entry for alice exists:

   "alice" Cleartext-Password := "passme"

2. Restart the FreeRADIUS server in debug mode and authenticate as alice. Observe the output of the FreeRADIUS server. The following should be part of the output:

   [suffix] No '@' in User-Name = "alice", looking up realm NULL
   [suffix] No such realm "NULL"
   ++[suffix] returns noop
   

What just happened?

We have done a normal authentication against the users file—nothing new here. We will, however, be focusing on a module inside the authorize section...