Reference Documentation

The full syntax of unlang is described in this section. Packets are processed via the Unlang Policy Language, also referred to as unlang. Policies allow the server to read information in databases, perform if / then / else checks, add content to replies, along with many other actions.

Many data type definitions are packaged in the FreeRADIUS server. These definitions are strongly typed. That is, each attribute has a pre-defined data type. For example, an attribute "Framed-IP-Address" has data type ipaddr.

Dynamic expansions may also be referred to as "xlats" for historical reasons.When processing packets, it’s possible to call functions or do string manipulation with attribute contents. The dynamic expansion documentation describes how this is done.

Where attribute names and data types are defined. During normal operation, the server receives packets of information from the network. Data in the packets is usually encoded in pre-defined "attributes" (RADIUS), or "options" (DHCP). The definitions are loaded from dictionary files.

The server includes a large number of configuration files. These files are automatically converted to HTML for the on-line documentation.

The FreeRADIUS server uses modules to manage different functions and tasks. Most of the modules are enabled ensuring compatibility with most authentication protocols. FreeRADIUS supports conditional module loading, enhancing flexibility and configuration management.

Contains policies, written in unlang, that determine how the server processes messages. For example, policy.d/debug determines what information to print to the terminal when the server is run in debug mode. >It’s important to note that the policy.d directory is not the only place containing policies. Policies are anything written in Unlang, throughout the configuration files, which describes how data should be processed as it flows through the processing sections.

Describes how configuration files are used to manage virtual servers in FreeRADIUS. Each virtual server has its own configuration file, ensuring settings organized and easy to manage. FreeRADIUS provides default configurations for over 30 virtual servers, giving users a wide range of ready-to-use examples and templates.

These man pages are for quick reference and maintaining compatibility over time. You can type man radiusd on the command line to access the same information. The man pages offer concise summaries of their features.