By default the session length for a client side and admin user are 1 hour. This means that when a client/admin is logged in after one hour of unbroken inactivity on the site their session will be expired from the software. Once their session has been removed from the software they will need to re-login the next time they return to the site. You as the admin have control over that "session removal time". You can shorten or lengthen that removal time. To control that time look to the following admin tool:

ADMIN TOOLS & SETTINGS > SECURITY SETTINGS > GENERAL SECURITY SETTINGS > SESSION TIME OUT ADMIN SIDE
ADMIN TOOLS & SETTINGS > SECURITY SETTINGS > GENERAL SECURITY SETTINGS > SESSION TIME OUT CLIENT SIDE

Look to the following screenshot:

Within that screenshot you'll see the admin tool location pointed out and the control itself. Those settings are set in seconds of life from last "touch" of the software/site before the session is removed. By default that value is "3600 seconds" which is hour. Within the screenshot we show an example of one full day (24 hours). Change that value to something else if you like. You have different controls for admin tool and client side.

<tip c n>Note that the statistic produced in the PAGE MODULES > MISC > Total Live Users (!MODULE_TOTAL_LIVE_USERS!) module does a count of the current users in the geodesic_sessions database table. This table contains all of the sessions mentioned above. Increasing or decreasing the session time-out on the client side will have an effect on the statistic produced by this module. Increasing the session time out time increases the amount of time before a session is removed from the geodesic_sessions table and thereby increasing the number of sessions/users that will be in the database at any one time. Also reducing the session time-out will reduce the number of users/sessions within the database at any one time. If you were to double the default session time-out value to just 7200 seconds would conceivably double the count of sessions counted in this statistic.</tip>

<tip c n>Also note that if a specific clients browser has a problem saving/returning cookies or has set their browser to refuse cookies can inflate this statistic quite a bit. All it takes is one of these users to visit 50 pages on your site to inflate the session count by that much.</tip>