When this plugin is active and the option enabled, it checks for a logged in user. If the visitor is not logged in, then the user is redirected to another site as defined in the redirect path option or will display a page with message as entered on from the settings. If logged in, site acts as normal.
Sites with this plugin active must access the site with sitename/wp-admin and log in.
Install the plugin
Go to the settings page
Set the address for the redirect
The active/inactive switch allows temporary disabling of the plugin