Hello, When 2 users with same username try to login to the server at the same time; Radius server receives Auth and Acct packets in the following order: 1- Auth from user1 2- Auth from user2 3- Acct from user1 4- Acct from user2 Since the session database is not populated until a user sends an accounting packet (using radutmp or sql modules) How can we prevent multiple login in this situation? shall we think in adding a record to the session database in authorization section? I am using freeradius-2.1.6 configurations ============= authorize { preprocess chap suffix files sql pap } preacct { preprocess acct_unique suffix files } accounting { # radutmp sql } session { # radutmp sql } Thanks, Houssam