rlm_counter - FreeRADIUS Module
The rlm_counter module provides a general framework to allow access based
on accumulated usage of a resource, such as total time online in a given
period, total data transferred in a given period, etc. This is very useful in
a 'Prepaid Service' situation, where a user has paid for a finite amount of
usage and should not be allowed to use more than that service. Collection,
monitoring, and replenishment of prepaid services are beyond the scope of this
The main configuration items to be aware of are:
- The filename where the usage data is stored.
- An attribute which will be present in the Access-Request to be used as the
'index' value for the counter. A counter entry is tracked for each unique
key. The most likely key you will want to use is User-Name.
- An attribute which will be used to increment the counter value. If this
attribute is Acct-Session-Time or an integer value the counter data is
incremented by the Attribute value. For all other attribute types the
counter is incremented by one.
- How frequently the counter data should be set back to 0. Valid values for
this variable are: hourly, daily, weekly,
monthly, ornever Alternatively, it can be user defined, in
the form: num[hdwm]. num is a numeric value, followed by one or none of
the following letters. h: hours, d: days, w: weeks, m: months.
- This defines an attribute name which will be registered by the counter
module and can be used to set the maximum allowed value for the counter
after which the user is rejected. If Daily-Session-Time is set, you can
use the following syntax in the Users file to set a cap of 3600 seconds (
8 hours ):
DEFAULT Max-Daily-Session := 3600
- This is the name of the attribute which will contain the remaining value
for the counter in the reply packet when the user is successfully
authorized. The default attribute name is
- This can be used to only apply the limitations to specific service types
of sessions. For example, setting this to Framed-User will only apply the
counter module to Framed sessions, excluding other types such as Telnet or
- The maximum size of the cache to be used by the module. The default is
This module registers an attribute, so it should be added to the instantiate
section, to be called on server startup. When used in the authorize section,
it must come after any modules which set the 'check_name' attribute.
instantiate, authorize, accounting
Chris Parker, email@example.com