NAME

       radrelay.conf - configuration file for the FreeRADIUS server "radrelay" personality

DESCRIPTION

       The  radrelay.conf  file  resides  in  the radius database directory, by default /etc/freeradius/3.0.  It
       defines the global configuration for the FreeRADIUS server, when the server is operating as "radrelay".

FILE FORMAT

       For a detailed description of the file format, see "man radiusd.conf".   The  configuration  entries  are
       much the same for radrelay.conf, with a few differences as noted here.

REPLICATION FOR BACKUPS

       Many sites run multiple radius servers; at least one primary and one backup server. When the primary goes
       down, most NASes detect that and switch to the backup server.

       That  will  cause  your  accounting packets to go to the backup server - and some NASes don't even switch
       back to the primary server when it comes back up.

       The result is that accounting records are missed, and/or the administrator must  jump  through  hoops  in
       order  to  combine  the  different  detail  files  from  multiple servers. It also means that the session
       database ("radutmp", used for radwho and simultaneous use detection) gets out of sync.

       radrelay solves this issue by "relaying" packets from one server to another, so they both have  the  same
       set of accounting data.

BUFFERING FOR HIGH-LOAD SERVERS

       If  the RADIUS server suddenly receives a many accounting packets, there may be insufficient CPU power to
       process them all in a timely manner.  This problem is especially noticeable when the  accounting  packets
       are going to a back-end database.

       Similarly,  you  may  have  one  database that tracks "live" sessions, and another that tracks historical
       accounting data.  In that case, accessing the first database is fast, as  it  is  small.   Accessing  the
       second  database  many  be slower, as it may contain multiple gigabytes of data.  In addition, writing to
       the first database in a timely manner is important, while data may be written to the second database with
       a few minutes delay, without any harm being done.

RELAYING OF ACCOUNTING PACKETS

       The radrelay.conf file controls the "radrelay" personality of the server, which can perform both  of  the
       functions above at the same time.

USAGE

       First,  you  should configure the main radius server to log to an extra, single detail file.  This may be
       done by adding an extra instance of the detail module to radiusd.conf:

       For example:

            detail radrelay-detail {
                 filename = ${radacctdir}/radrelay/detail
                 permissions = 0600
                 dir_permissions = 0755
                 locking = yes
            }
            ...
            accounting {
                 ...
                 radrelay-detail
                 ...
            }
       This configuration will cause accounting packets to be logged to the ${radacctdir}/radrelay/detail  file.
       This  file  should not be rotated by standard log rotation scripts, as the radrelay program will read and
       rotate it.

RADRELAY.CONF EXAMPLE

       See the radrelay.conf file for detailed instructions on configuration entries, what they mean, and how to
       use them.

       To have the "radrelay" portion of the server read the above detail file, configure radrelay.conf with the
       following section:

            listen {
                 type = detail
                 filename = ${radacctdir}/radrelay/detail
                 max_outstanding = 100
                 identity = radrelay
            }

       The server will read the accounting packets from the detail file, and process them  just  as  if  it  had
       received them from the NAS.  Therefore, you should configure the "accounting" section of radrelay.conf to
       write the accounting records to an "sql" module, or to proxy them to another RADIUS server.

       Then, start the server via the following command:

       $ radiusd -n radrelay

       The server should start up, read the detail file, and process accounting packets from it.

NOTES

       The  radiusd.conf  file  is  not  read  at  all  when  the  server  is  running as radrelay.  Please edit
       radrelay.conf.

CREDITS

       The original "radrelay" program was written by Miquel van Smoorenburg for the Cistron radius project, and
       ported to FreeRADIUS by Simon Ekstrand.  The "radsqlrelay" was written by Kostas Kalavras.  It was  never
       released  as  part  of  an  official  FreeRADIUS  release,  but  served as a basis for the design of this
       implementation.

FILES

       /etc/freeradius/3.0/radrelay.conf

SEE ALSO

       radiusd(8), radiusd.conf(5)

AUTHOR

       Alan DeKok <aland@ox.org>

                                                   27 May 2005                                  radrelay.conf(5)