Identifying root causes for an issue can be tedious for site administrators. Moodle logs every activity done by a user including what they click on and stores it in a log.
Logs are really helpful to troubleshoot issues where something was working before and had stopped. Apart from details about changes, a log shows who the change was made by, when it was made, who was affected and the origin of the change.
These logs are available in:
2. Course level
3. Site level
To identify any issue it is important to see which log you are looking at.
Activity level logs
You can access activity logs from Course> open activity > select Reports under course administration > logs
If you seem to face a problem with an activity not being completed or incorrect details for an activity being shown on a report, you will need to look at activity logs.
One of the most common issues with activities is when administrators, teachers or any user that has permissions to change the activity settings make changes to the settings after a student has completed an activity.
Course level logs
You can access course logs from Cours > select Reports under course administration > logs
Course logs help in troubleshooting the outcome of a course. You can see if someone has made changes to enrolments, dates, course level settings etc.
An example for where this log is helpful is if a user changes course completion settings and students are not able to complete the course, a web API making changes to enrolment dates for students and students losing access.
Site level logs
A log of site activity may be generated by a site administrator in Administration>Site administration>Reports>Logs
The log can display all activities, site news or site errors, such as failed login attempts, and all levels.
Additional References:
https://docs.moodle.org/35/en/Logs
https://docs.moodle.org/35/en/Logging