radrelay.conf(5) FreeRADIUS configuration file radrelay.conf(5)NAMEradrelay.conf - configuration file for the FreeRADIUS server "radrelay"
personality
DESCRIPTION
The radrelay.conf file resides in the radius database directory, by
default /etc/raddb. 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 the 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 adminis‐
trator 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 noticable 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, access‐
ing 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 impor‐
tant, while data may be written to the second database with a few min‐
utes 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 {
detailfile = ${radacctdir}/radrelay/detail
detailperm = 0600
dirperm = 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
detail = ${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 account‐
ing 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 offical FreeRADIUS release, but served as
a basis for the design of this implementation.
FILES
/etc/raddb/radrelay.conf
SEE ALSOradiusd(8), radiusd.conf(5)AUTHOR
Alan DeKok <aland@ox.org>
27 May 2005 radrelay.conf(5)
