Moodle's database authentication plugin allows Moodle to use a table in an external database to check a user's name and password. The external table enables you to use the usernames and passwords in an application like Peoplesoft or a portal system like Drupal. The plugin is relatively simple, but very flexible. All you need is a database table with your usernames, passwords and any profile fields you want to import into Moodle. Give Moodle access to the table (it can be read-only access to ensure the table can only be changed by your external authority) and your users can use their passwords from your other application to log in to Moodle.
To set up Moodle's database authentication plugin:
Login to your Moodle as an administrator.
From the Site administration menu, select Plugins. Then select Authentication.
You will now be on the Manage authentication page. You will see a list of available authentication plugins. To enable the Database...