Saya pakai radius versi 2.0.5.
Untuk disable mutli login saya buat dokumentasi/catatan di bawah ini berdasarkan http://wiki.freeradius.org/SQL_HOWTO

Buat file data.sql seperti di bawah ini:
# Define group and put into radgroupcheck
INSERT INTO radgroupcheck (GroupName, Attribute, op, Value) values(“hotspot”,”Simultaneous-Use”,”:=”, “1″);
# Add user radius into radcheck
INSERT INTO radcheck (UserName, Attribute, Value) VALUES (‘yudi’, ‘Password’, ‘xxxx);
INSERT INTO radcheck (UserName, Attribute, Value) VALUES (‘dani’, ‘Password’, ‘xxxx’);
INSERT INTO radcheck (UserName, Attribute, Value) VALUES (‘awan’, ‘Password’, ‘xxxx’);
INSERT INTO radcheck (UserName, Attribute, Value) VALUES (‘hendry’, ‘Password’, ‘xxxx’);
# Add user into group radusergroup
INSERT INTO radusergroup (username, groupname) VALUES (‘yudi’, ‘hotspot’);
INSERT INTO radusergroup (username, groupname) VALUES (‘dani’, ‘hotspot’);
INSERT INTO radusergroup (username, groupname) VALUES (‘awan’, ‘hotspot’);
INSERT INTO radusergroup (username, groupname) VALUES (‘hendry’, ‘hotspot’);

Kemudian jalankan mysql dan isi dengan data.sql di atas:
mysql -u radius -ppassword radius < data.sql

Tambahkan baris di bawah ini ke /etc/freeradius/users:

DEFAULT Group == "staff", Simultaneous-Use := 4
Fall-Through = 1
DEFAULT Group == "business", Simultaneous-Use := 2
Fall-Through = 1
DEFAULT Group == "hotspot", Simultaneous-Use := 1
Fall-Through = 1
DEFAULT Simultaneous-Use := 1
Fall-Through = 1