[rad] Re: Change of Authorization (RFC 3576 / 5176)

[Ivan Kalik]

> On Thu, 11 Jun 2009, Fajar A. Nugraha wrote:
>> If I'm reading Alan's post correctly, freeradius supports CoA packets,
>> but you need to write your own rule/policy to send it. For
>> over-bandwidth scenario, the rule should be while examining
>> interim-update acct packets...
>
> I've never heard of these...

http://freeradius.org/rfc/rfc2869.html#Acct-Interim-Interval

> How often are they sent to a radius server
> during a dialup call (AS5400)?

As often as you feel like it. There usually isn't a default set. You can
also set it (fix it) in Cisco configuration.

> Into what section could I put a script so
> that it triggers only on interim updates?

Accounting. See man unlang to find out how to execute only on chosen packets.

> I wouldn't mind being able to
> dynamically extend a caller's session if they buy more time online....

You would normaly use radius *client* to send CoA for administrative event
(like this one). You would use server for a network event (like you can't
be bothered to write a script that updates customer session for online
payment - you just recaclulate session duration on every accounting update
to see if anything changed; that's poor administration - lots of wasted
CPU time). Server is more commonly used to send CoA on accounting updates
for vendors that have support for CoA but not for session bandwidth/data
limiters.

Ivan Kalik
Kalik Informatika ISP