For those interested, here the solution I am using now: I am using FR 1.0.5 with MySQL 4.1.10a, PHP and no flat files, except for the DEFAULT values and the standard configuration files radiusd.conf, sql.conf (my NAS list is also in a SQL table). I also changed most of the SQL column names, by adding a prefix. For the examples I changed it back to the original names. How to get user online status: ============================== 1. Add the TIMESTAMP column to the radacct table `radacct_mdate` timestamp NULL default CURRENT_TIMESTAMP on update CURRENT_TIMESTAMP 2. To get the online status set up a query something like this (using PHP): define('RAD_ONLINE_TIMEOUT', 15); // 15 min since last timestamp from NAS, assuming connection dead $query = "SELECT COUNT(*) FROM radacct WHERE UserName = ' . $username . ' AND AcctStopTime=0 AND DATE_SUB(NOW(),INTERVAL ' . RAD_ONLINE_TIMEOUT .' MINUTE) <= radacct_mdate ORDER BY AcctStartTime DESC LIMIT 1)"; My actual query is a bit more complicated as I verify against a user table if they are actually allowed to be online ( Starttime < ActualTime < Stoptime) How to get Simultaneous-Use with FR & MySQL working: ==================================================== 1. I setup my defaults in the raddb/users file (at the very end and nothing else beside localhost) DEFAULT Simultaneous-Use := 1, Auth-Type := SQL (this seems to be the only way) Idle-Timeout = 3600, Acct-Interim-Interval = 180 Note: You can override the default Simultaneous-Use attribute for a user or a group by setting it in radcheck or radgroupcheck table (groupname Simultaneous-Use := 3). 2. In raddb/radiusd.conf Instead of using radutmp, I am using SQL: accounting { . . sql } session { # See "Simultaneous Use Checking Querie" in sql.conf sql } 3. In raddb/sql.conf simul_count_query = "SELECT COUNT(*) FROM ${acct_table1} WHERE UserName='%{SQL-User-Name}' AND AcctStopTime=0 AND CallingStationId <> '%{Calling-Station-Id}' AND DATE_SUB(NOW(),INTERVAL 15 MINUTE) <= radacct_mdate" simul_verify_query = "SELECT RadAcctId, AcctSessionId, UserName, NASIPAddress, NASPortId, FramedIPAddress, CallingStationId, FramedProtocol FROM ${acct_table1} WHERE UserName='%{SQL-User-Name}' AND AcctStopTime = 0 AND CallingStationId <> '%{Calling-Station-Id}' AND DATE_SUB(NOW(),INTERVAL 15 MINUTE) <= radacct_mdate" Not sure that this is all 100% like the developers intended it to be, but it works. Gunther