radiusd(8)

NAME

radiusd - Authentication, Authorization and Accounting server

SYNOPSIS

radiusd [-C] [-d config_directory] [-f] [-h] [-l log_file] [-m] [-n name] [-s] [-t] [-T] [-v] [-x] [-X]

DESCRIPTION

FreeRADIUS is a high-performance and highly configurable RADIUS server. It supports many database back-ends such as flat-text files, SQL, LDAP, Perl, Python, etc. It also supports many authentication protocols such as PAP, CHAP, MS-CHAP(v2), HTTP Digest, and EAP (EAP-MD5, EAP-TLS, PEAP, EAP-TTLS, EAP-SIM, etc.).

It also has full support for Cisco’s VLAN Query Protocol (VMPS) and DHCP.

Please read the DEBUGGING section below. It contains instructions for quickly configuring the server for your local system.

OPTIONS

The following command-line options are accepted by the server.

-C: Check the configuration and exit immediately. If there is a problem reading the configuration, then the server will exit with a non-zero status code. If the configuration appears to be acceptable, then the server will exit with a zero status code.

Note that there are limitations to this check. Due to the complexities involved in almost starting a RADIUS server, these checks are necessarily incomplete. The server can return a zero status code when run with -C, but may still exit with an error when run normally.

See the output of radiusd -XC for a list of which modules are checked for correct configuration, and which modules are skipped, and therefore not checked.
-d config_directory: Defaults to /etc/raddb. Radiusd looks here for its configuration files such as the dictionary and the users files.
-f: Do not fork, stay running as a foreground process.
-h: Print usage help information.
-l log_file: Defaults to ${logdir}/radius.log. Radiusd writes its logging information to this file. If log_file is the string stdout, then logging messages will be written to stdout.
-m: On SIGINT or SIGQUIT exit cleanly instead of immediately. This is most useful for when running the server with "valgrind".
-n name: Read raddb/name.conf instead of raddb/radiusd.conf.

Note that by default, the server looks for a configuration file which matches its own name. Creating a soft link from file foo to radiusd, and then running the program foo, will cause the binary to look for raddb/foo.conf.
-s: Run in "single server" mode. The server normally runs with multiple threads and/or processes, which can lower its response time to requests. In single server mode, the server will not "daemonize" (auto-background) itself.
-t: Do not spawn threads.
-T: Always add timestamps to log messages.
-v: Print server version information and exit.
-X: Debugging mode. This argument is equivalent to using -sfxx -l stdout. When trying to understand how the server works, ALWAYS run it with radiusd -X. For production servers, use the raddebug program.
-x: Finer-grained debug mode. In this mode the server will print details of every request to the default logging destination. Using multiple -x options will increase the debug output.

DEBUGGING

The default configuration is set to work in the widest possible circumstances. It requires minimal changes for your system.

However, your needs may be complex, and may require significant changes to the server configuration. Making random changes is a guaranteed method of failure. Instead, we STRONGLY RECOMMEND proceeding via the following steps:

1) Always run the server in debugging mode ( radiusd -X ) after making a configuration change. We cannot emphasize this enough. If you are not running the server in debugging mode, you will not be able to see what is doing, and you will not be able to correct any problems.

If you ask questions on the mailing list, the first response will be to tell you "run the server in debugging mode". Please, follow these instructions.

2) Change as little as possible in the default configuration files. The server contains a decade of experience with protocols, databases, and different systems. Its default configuration is designed to work almost everywhere, and to do almost everything you need.

3) When you make a small change, testing it before changing anything else. If the change works, save a copy of the configuration, and make another change. If the change doesn’t work, debug it, and try to understand why it doesn’t work.

If you begin by making large changes to the server configuration, it will never work, and you will never be able to debug the problem.

4) If you need to add a connection to a database FOO (e.g. LDAP or SQL), then:
a) Edit raddb/modules/foo
This file contains the default configuration for the module. It contains comments describing what can be configured, and what those configuration entries mean.
b) Edit raddb/sites-available/default
This file contains the default policy for the server. e.g. "enable CHAP, MS-CHAP, and EAP authentication". Look in this file for all references to your module "foo". Read the comments, and remove the leading hash '#' from the lines referencing the module. This enables the module.
c) Edit raddb/sites-available/inner-tunnel
This file contains the default policy for the "tunneled" portion of certain EAP methods. Perform the same kind of edits as above, for the "default" file.. If you are not using EAP (802.1X), then this step can be skipped.
d) Start the server in debugging mode ( radiusd -X ), and start testing.

5) Ask questions on the mailing list
(freeradius-users@lists.freeradius.org). When asking questions, include the output from debugging mode ( radiusd -X ). This information will allow people to help you. If you do not include it, the first response to your message will be "post the output of debug mode".

Ask questions earlier, rather than later. If you cannot solve a problem in a day, ask a question on the mailing list. Most questions have been seen before, and can be answered quickly.

BACKGROUND

RADIUS is a protocol spoken between an access server, typically a device connected to several modems or ISDN lines, and a radius server. When a user connects to the access server, (s)he is asked for a loginname and a password. This information is then sent to the radius server. The server replies with "access denied", or "access OK". In the latter case login information is sent along, such as the IP address in the case of a PPP connection.

CONFIGURATION

radiusd uses a number of configuration files. Each file has its own manpage describing the format of the file. These files are:

radiusd.conf: The main configuration file, which sets the administrator-controlled items.
dictionary: This file is usually static. It defines all the possible RADIUS attributes used in the other configuration files. You don’t have to modify it. It includes other dictionary files in the same directory.
unlang: The processing and policy language used in the server.

AUTHOR

The FreeRADIUS Server Project (https://freeradius.org)