Maintenance mode
From MoodleDocs
The idea of maintenance mode is to prevent any users other than admin to use the site while the maintenance process takes place.
When students/guests/teachers try access a course in maintenance mode, they will obtain a message saying the course is in maintenance mode. A customized message may be added, perhaps stating when the site will be available again or giving the reason for doing maintenance.
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See also
- Using Moodle Maintenance mode? forum discussion