User Session & accounting management

[Suresh Kumar Subramanian]

Hi,

I am newbie and I have couple of questions in the free radius.

1)
How do we maintain the session time in free radius?

For example, a given user the session time is configured for 1 hour.
After 1 hour, radius server should initiate "Session disconnect message" for the user to the NAS.
I understand that, Freeradius does support "session disconnect message", but we can achieve this with radclient utility.
Ref: http://wiki.freeradius.org/protocol/Disconnect-Messages

Here my problem is, how the session timeout is identified to trigger this disconnect message?
Please help.

2) where freeradius logs the  accounting information?  I have not configured the mysql. Does freeradius supports flat file for storing accounting records.?

Thanks
Suresh.