Data Types

The configuration directives can be one of a number of pre-defined data types. These data types are similar to the ones in the dictionaries, however they are not always the same.

The dictionary data types are limited because the data needs to be encoded in a RADIUS packet. The dictionaries also need to follow the RADIUS standards, which means that the number of data types is limited.

The data types in the configuration files have no such limitations. For example, in RADIUS packets, a string can be no more than 253 characters. In the configuration files, it can be nearly unlimied. The configuration files also have data types such as boolean, which cannot appear in a RADIUS packet. Some RADIUS data types such as octets cannot appear in the configuration files.

When the server parses a configuration directive such as foo = bar, the directive foo has a data type associated with it. The value bar is expected to match the format of that data type. When the value does not match, the server prints a descriptive error message, and does not start. The error must be corrected before the server will operate.

The configuration files can contain the data types given in the following table.

Data Type Description


true / false values.


decimal numbers


names of files


unsigned integers.


IP addresses


printable strings