Authentication: Unique Login
auth_uniquelogin
Maintained by 
António Vilela
This authentication plug-in prevents that each one Moodle user has more than one active session simultaneously.
593 sites
467 downloads
24 fans
Current versions available: 3
The goal of this authentication plug-in is to make sure that each user in Moodle only has one active session simultaneously.
To work properly, the plugin needs that Database-stored sessions are enabled. Have a look at the module documentation on http://docs.moodle.org/20/en/Uniquelogin_authentication to more information.
This plugin is being maintained by ED-ROM, the portuguese Moodle Partner.
Screenshots
Contributors
António Vilela (Lead maintainer): Maintainer
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l have tried the plugin by following the instructions, its still not working. here is my scenario.
lam using moodle version 3.2.2. l have downloaded and activated the plugin.l have Enabled the setting to Use database for session information.
l have moved the plugin up. it only remains on the third position, having "Manual accounts - as position one" and "No login - as position two".
l then tested the plugin by login into different computers using the same login details, as a student, the plugin didnt stop me or hinder me by giving me "you are already logged in" kind of message. is there anything l forgot to do to make this plug not work for me? By the way, l manually register all my students to moodle. Thank you
The old session is turned off. In other words, the plugin affects the session you have in the other browser.
It does not prevent user to login.
thank you for your quick response. so in a nutshell it means that this plugin cannot give me what lam looking for, what l want to achieve is prevent multiple login in moodle using the same login details. lam trying to avoid students sharing their login details with their friends because lam running a membership based Learning Management System. l have also tried to use the settings: Admin > Plugins > Authentication > Manage Authentication >limit the number of concurrent logins for a user (l set it to one. and still doesn't work.) Any advice to achieve this functionality would be highly appreciated. Thank you.
You can think about using Facebook login with a plugin available to this purpose, and prevent other authentication forms. Nobody likes to share his Facebook credentials with friends.
thank you for your feedback Sir. l was even considering using OAuth_2_authentication, where by students can login using their gmail, facebook accounts. Then it crossed my mind that some students can easily create those accounts only to use it in moodle, hence having no absolute problem in sharing it with their friends. Since those facebook and gmail will only be created to be used in moodle login only. its a very tricky situation. l wonder how others have gone around this especially those who are offering paid membership courses to their students. For now lam stuck, but l will keep on searching hope to get something soon.
l think you have a point there and l think thats my best bet. l will definitely work towards that direction. the facebook and gmail login. Ang again, thank you very much for dedicating you time to help me get the solution. Thank you António.
l would like to thank you for taking your time, all the efforts you made to point me to the right direction. As you have suggested. l have decided to use the OAuth 2 authentication which works like a charm! for those who are interested here is the link: https://docs.moodle.org/36/en/OAuth_2_authentication and here is my login page to my moodle LMS (having incorporated facebook and Google login) https://asifunde.co.za/asifunde/login/index.php
You are welcome. Happy to know you found a solution!
The plug-in will not work because SAML send the user out of moodle to login.
Is it not compatible with 3.7?
@Vijaya Kumar Do not set Unique Login as a user authentication method. Please see the correct use in https://docs.moodle.org/20/en/Uniquelogin_authentication