Section 3. Configuring Radiator

3. Configuring Radiator

This section describes the Radiator configuration file and the statements that control the behaviour of the Radiator server, radiusd.

When radiusd starts, it reads the configuration file. The default file name and path for the configuration file depends on the operating system and how Radiator is installed.

Unix and macOS: /etc/radiator/radius.cfg or radiator.conf
Windows: C:\Program Files\Radiator\radius.cfg or radiator.conf

Radiator deb, RPM and Windows MSI packages use startup configuration that uses radiator.conf to be consistent with log directory, package name and other names.

You can specify an alternate configuration file with radiusd's -config_file command line parameter. There is a test configuration file (radius.cfg) in the Radiator distribution that shows most of parameters and clauses that you can use in a configuration file, and examples of how to use them. There is also a very simple example (simple.cfg) in the goodies/ directory in the Radiator distribution. It is a good starting point for your own configuration file.

In general terms, the configuration file allows you control the following things:

Behaviour of the server in general, including logging
Which RADIUS clients the server responds to
Which RADIUS realms the server works with
Handlers for specifying special ways to handle requests
For each realm, what methods are used for authenticating users and storing accounting information
For each authentication method for each realm, the configuration of the authentication module
Custom Perl hooks that are run during the processing of each request. For more information, see Section 14. Execution sequence and hook processing

The configuration file is an ASCII text file, it can be edited by any text editor. Leading white space in each line is ignored, so you can use indentation to make your configuration file easier to read. Case is important in all parameter names and clauses.

Tip

An alternative to editing the configuration file directly is to use the ServerHTTP clause (for more information, see Section 3.121. <ServerHTTP> and Section 10. Configuring Radiator with GUI) which allows you to connect to Radiator with standard web browser and examine, change and test the configuration with an easy to use point and click web interface.

The configuration file consist of the following things:

Comment line
The comment line starts with a # as the first character. Anything including and after the # is ignored. Blank lines are also ignored. Here is an example:
```
# This is a comment
```
CAUTION
Comments that do not start at the beginning of the line are likely to be taken as part of a parameter value:
```
SomeParameter xxxxxx # INCORRECT:this is not a comment
```
Parameter setting
The first word is the name of the parameter to set, all the following words and digits are the value to be used for the parameter. All the parameters you can set in the configuration file are described in this document. Here is an example:
```
Trace 4
```
Parameter setting from file
Parameter values can be retrieved from an external file. The line consist of the parameter name and filename, here is the format:
```
parameter file:"filename"
```
This is a useful feature for putting long parameters, such as a hook, in an external file. Here is an example that loads the code for PreAuthHook from the external file hook.pl:
```
PreAuthHook file:"hook.pl"
```
Parameter setting from SQL database query.
Parameter values can be retrieved from an SQL database. The line consist of the parameter name, SQL identifier, and SQL query, here is the format:
```
ParameterName sql:identifier:query
```
It looks for a previously defined <AuthBy SQL> clause with an Identifier and runs the given SQL query. The first row in the result is used to set the parameter. The SQL database lookup is only done once at startup time. Here is an example of using the SQL query:
```
<AuthBy SQL>
      Identifier        myidentifier
      DBSource          dbi:mysql:radius
      DBUsername        mikem
      DBAuth            fred
</AuthBy>
Trace sql:myidentifier:select value from configuration where\ 
      name = 'Trace'
```
Start or end of clause
A clause is a collection of parameter settings related to a single feature in the server. The first line in a clause is surrounded by angle brackets, for example <Client fred>, which marks the beginning of the configuration for client with the DNS name "fred". Subsequent lines are interpreted as parameter settings for the feature, until the end of the clause is seen. The end of the clause is surrounded by angle brackets with a slash. Here is a usage example:
```
<Client DEFAULT>
      # Configuration parameters for the Client go here
      .....
</Client>
```

3. Configuring Radiator

Tip

CAUTION