Hello every body I made all important configuration to allow Simultaneous-Use attribute working without result . Modify the /etc/freeradius/sql/mysql/dialup.conf file and unncomment : simul_count_query = "SELECT COUNT(*) \ FROM ${acct_table1} \ WHERE username = '%{SQL-User-Name}' \ AND acctstoptime IS NULL" This is the result when I run freeradius in debug mode , there are no any check for simultaneous-use attribute rad_recv: Accounting-Request packet from host 10.10.0.130 port 1049, id=231, length=104 Acct-Status-Type = Start Acct-Session-Id = "3a457fb2" User-Name = "99625743140" NAS-Identifier = "ftg" Framed-IP-Address = 192.168.33.5 Fortinet-Client-IP-Address = 192.168.33.5 Fortinet-Vdom-Name = "root" Calling-Station-Id = "192.168.33.5" Event-Timestamp = "Mar 8 2018 12:32:49 +03" # Executing section preacct from file /etc/freeradius/sites-enabled/default +group preacct { ++[preprocess] = ok [acct_unique] WARNING: Attribute NAS-Port was not found in request, unique ID MAY be inconsistent [acct_unique] Hashing ',NAS-Identifier = "ftg",NAS-IP-Address = 10.10.0.130,Acct-Session-Id = "3a457fb2",User-Name = "99625743140"' [acct_unique] Acct-Unique-Session-ID = "cd2730cfc5c2adb4". ++[acct_unique] = ok [suffix] No '@' in User-Name = "99625743140", looking up realm NULL [suffix] No such realm "NULL" ++[suffix] = noop +} # group preacct = ok # Executing section accounting from file /etc/freeradius/sites-enabled/default +group accounting { [detail] expand: %{Packet-Src-IP-Address} -> 10.10.0.130 [detail] expand: /var/log/freeradius/radacct/%{%{Packet-Src-IP-Address}:-%{Packet-Src-IPv6-Address}}/detail-%Y%m%d -> /var/log/freeradius/radacct/10.10.0.130/detail-20180308 [detail] /var/log/freeradius/radacct/%{%{Packet-Src-IP-Address}:-%{Packet-Src-IPv6-Address}}/detail-%Y%m%d expands to /var/log/freeradius/radacct/10.10.0.130/detail-20180308 [detail] expand: %t -> Thu Mar 8 12:32:49 2018 ++[detail] = ok [sradutmp] expand: /var/log/freeradius/sradutmp -> /var/log/freeradius/sradutmp [sradutmp] expand: %{User-Name} -> 99625743140 rlm_radutmp: No NAS-Port seen. Cannot do anything. rlm_radumtp: WARNING: checkrad will probably not work! ++[sradutmp] = noop [sql] expand: %{User-Name} -> 99625743140 [sql] sql_set_user escaped user --> '99625743140' [sql] expand: %{Acct-Delay-Time} -> [sql] ... expanding second conditional [sql] expand: INSERT INTO radacct (acctsessionid, acctuniqueid, username, realm, nasipaddress, nasportid, nasporttype, acctstarttime, acctstoptime, acctsessiontime, acctauthentic, connectinfo_start, connectinfo_stop, acctinputoctets, acctoutputoctets, calledstationid, callingstationid, acctterminatecause, servicetype, framedprotocol, framedipaddress, acctstartdelay, acctstopdelay, xascendsessionsvrkey) VALUES ('%{Acct-Session-Id}', '%{Acct-Unique-Session-Id}', '%{SQL-User-Name}', '%{Realm}', '%{NAS-IP-Address}', '%{NAS-Port}', '%{NAS-Port-Type}', '%S', NULL, '0', '%{Acct-Authentic}', '%{Connect-Info}', '', '0', '0', '%{Called-Station-Id}', '%{Calling-Station-Id}', '', '%{Service-Type}', '%{Framed-Protocol}', '%{Framed-IP-Address}', rlm_sql (sql): Reserving sql socket id: 10 rlm_sql (sql): Released sql socket id: 10 ++[sql] = ok ++update control { sql_xlat expand: %{User-Name} -> 99625743140 sql_set_user escaped user --> '99625743140' expand: SELECT (SUM(acctinputoctets)+SUM(acctoutputoctets)) AS Total FROM radacct where acctstarttime >= CURDATE() AND radacct.username='%{User-Name}' -> SELECT (SUM(acctinputoctets)+SUM(acctoutputoctets)) AS Total FROM radacct where acctstarttime >= CURDATE() AND radacct.username='99625743140' rlm_sql (sql): Reserving sql socket id: 9 sql_xlat finished rlm_sql (sql): Released sql socket id: 9 expand: %{sql:SELECT (SUM(acctinputoctets)+SUM(acctoutputoctets)) AS Total FROM radacct where acctstarttime >= CURDATE() AND radacct.username='%{User-Name}'} -> 115456 sql_xlat expand: %{User-Name} -> 99625743140 sql_set_user escaped user --> '99625743140' expand: SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='%{User-Name}' -> SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='99625743140' rlm_sql (sql): Reserving sql socket id: 8 SQL query did not return any results rlm_sql (sql): Released sql socket id: 8 expand: %{sql: SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='%{User-Name}'} -> sql_xlat expand: %{User-Name} -> 99625743140 sql_set_user escaped user --> '99625743140' expand: SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='%{User-Name}' -> SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='99625743140' rlm_sql (sql): Reserving sql socket id: 7 SQL query did not return any results rlm_sql (sql): Released sql socket id: 7 expand: %{sql: SELECT value FROM radcheck WHERE attribute='Ftg-Total-Limit' AND username='%{User-Name}'} -> sql_xlat expand: %{User-Name} -> 99625743140 sql_set_user escaped user --> '99625743140' expand: select calledstationid from radacct where acctsessionid='%{Acct-Session-Id}' -> select calledstationid from radacct where acctsessionid='3a457fb2' rlm_sql (sql): Reserving sql socket id: 6 sql_xlat finished rlm_sql (sql): Released sql socket id: 6 expand: %{sql:select calledstationid from radacct where acctsessionid='%{Acct-Session-Id}'} -> ++} # update control = noop ++? if ("%{control:Tmp-Integer-0}" > "%{control:Tmp-String-1}") expand: %{control:Tmp-Integer-0} -> 115456 expand: %{control:Tmp-String-1} -> ? Evaluating ("%{control:Tmp-Integer-0}" > "%{control:Tmp-String-1}") -> TRUE ++? if ("%{control:Tmp-Integer-0}" > "%{control:Tmp-String-1}") -> TRUE ++if ("%{control:Tmp-Integer-0}" > "%{control:Tmp-String-1}") { +++update coa { expand: %{User-Name} -> 99625743140 expand: %{Framed-IP-Address} -> 192.168.33.5 +++} # update coa = noop ++} # if ("%{control:Tmp-Integer-0}" > "%{control:Tmp-String-1}") = noop [attr_filter.accounting_response] expand: %{User-Name} -> 99625743140 attr_filter: Matched entry DEFAULT at line 12 ++[attr_filter.accounting_response] = updated +} # group accounting = updated Sending Accounting-Response of id 231 to 10.10.0.130 port 1049 WARNING: Empty pre-proxy section. Using default return values. Sending CoA-Request of id 235 to 10.10.0.130 port 3799 User-Name = "99625743140" Framed-IP-Address = 192.168.33.5 Finished request 2. Cleaning up request 2 ID 231 with timestamp +244 Going to the next request Waking up in 2.4 seconds. rad_recv: CoA-NAK packet from host 10.10.0.130 port 3799, id=235, length=50 Error-Cause = Session-Context-Not-Found Event-Timestamp = "Mar 8 2018 12:32:49 +03" Message-Authenticator = 0xdecd7dd3d4d82835f93f87c35704f1b9 # Executing section post-proxy from file /etc/freeradius/sites-enabled/default +group post-proxy { [eap] No pre-existing handler found ++[eap] = noop +} # group post-proxy = noop Finished request 2. Going to the next request Waking up in 2.9 seconds.