Marinko Tarlac mangia81 at
Sat Jan 24 20:50:12 CET 2009

I have another solution...

Add one field at the end of radacct table (LastUpdate for example), and 
choose datetime as a type.
Edit default queries in dialup.conf  (FR 2.x) od sql.conf  (FR <  2.x) 
and add '%S' in all update and insert queries. Now you will have the 
date and time from the last update and you can calculate which session 
was stalled. (for example, if you Interim-Update interval is 5 minutes 
and LastUpdate was 20min. from now, you can close session with cron script.

PHP for example:

$last_update = 10; // time in min
$this_moment = date ("Y-m-d H:i:s");

$close_sessions = mysql_query ("UPDATE radacct SET 
AcctTerminateCause='Stalled-Session',  AcctStopTime = AcctStartTime + 
INTERVAL AcctSessionTime SECOND WHERE AcctStopTime = '0000-00-00 
00:00:00' AND Vrijeme < '$this_moment' - INTERVAL '$last_update' MINUTE 
AND LastUpdate != '0000-00-00 00:00:00'") or die("Ops, I can't do 

Beware, I'm using old sql schema so you can see that opened sessions in 
my database has value 0000-00-00 00:00:00 and by default in 2.x version 
is NULL.

You need to tune up this options because it will depend from connection 
between your NAS(es) and radius server. If you have bad link, set up 
updates more often and cron script can check this on every 3 minutes.

For example, if your cron script starts every 2 minutes, you have 
updates on every 2 min and $last_update = 11;, script will close the 
session after 5-6 checks and it means your session wasn't updated in 
last 5-6 Interim-Updates and it is good idea to close it :)

Maybe I made a mistake in this calculations (working during last 24hrs) 
but you'll probably get the point.

tnt at wrote:
>> I would like to have more informations about the deletestalesessions
>> option of rlm_sql.
>> - What does it do?
>> - What's its behaviour?
>> - How does it achieve what it does?
> It's used with Simultaneous-Use checking. If checkrad script discovers a
> stale session (there is an open session for the user in radius database
> but NAS doesn't have him on that port) it can be removed (so it
> doesn't create the same situation when user connects next time).
> Ivan Kalik
> Kalik Informatika ISP
> -
> List info/subscribe/unsubscribe? See

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