This parameter allows you to apply a simple limit to the number of simultaneous sessions a user in this Realm is permitted to have. It is most common to limit users to either one session at a time or unlimited, but Radiator also supports other numbers.

MaxSessions works by looking at each accounting request for a realm when it arrives. Whenever Start is seen for a user, the count of their number if current sessions is incremented, and whenever a Stop is seen, it is decremented. When an access request is received, the number of sessions current for that user is compared to MaxSessions. If the user already has MaxSessions sessions or more, Radiator replies with an access denial. By setting MaxSessions to 0, you can temporarily deny access to all users in the realm.

MaxSessions applies a hard limit that cannot be overridden by DefaultSimultaneousUse parameter or by per-user Simultaneous-Use check items. For more information, see Section 3.32.14. DefaultSimultaneousUse. For many applications, you may wish to consider using DefaultSimultaneousUse instead of MaxSessions. You can control the maximum number of sessions on a per-user basis with the Simultaneous-Use check item. For more information, see Section 7.1.16. Simultaneous-Use.

The session count for each user is stored entirely within Radiator (unless you specify a SessionDatabase clause). This means that if you restart or reinitialise Radiator, it will lose count of the number of current sessions for each user. Radiator can use SNMP to confirm whether a user is already logged in or not. For more information, see Section 3.14.35. NasType.

Note that if Radiator fails to receive an accounting Stop request, it may result in incorrectly assume the users are not permitted to log in when, in fact, they are. Correct this by restarting Radiator, or by sending an artificial accounting stop for the user using the radpwtst utility or by configuring Radiator to query the NAS directly. For more information, see Section 6.1. radpwtst and Section 3.14.35. NasType.

# Limit all users in this realm to max of 1 session
MaxSessions 1