Plesk dashboard widget monitoring stuck: grafana has no rules loaded

Symptoms

• Plesk Obsidian running on a Debian-based operating system
• Configuring grafana in debug mode in /etc/grafana/grafana.ini shows no rules added:
  

  PLESK_INFO: logger=alerting.scheduler t=2025-02-12T12:33:31.008195604+01:00 level=debug msg="Scheduling update" ruleCount=0
  logger=alerting.scheduler t=2025-02-12T12:33:41.000957178+01:00 level=debug msg="Scheduling update" ruleCount=0
  logger=secrets t=2025-02-12T12:33:50.255870488+01:00 level=debug msg="Removing expired data keys from cache..." logger=secrets t=2025-02-12T12:33:50.256088386+01:00 level=debug msg="Removing expired data keys from cache finished successfully"

Cause

Grafana's installation is corrupted and this prevents the Grafana and Monitoring extensions in Plesk from working as expected because they both depend on Grafana being operational.

Resolution

1. Connect to the server via SSH

2. Remove the Grafana extension:

   # plesk bin extension --uninstall grafana

3. Remove the Monitoring extension by executing the following command:

   # plesk bin extension --uninstall monitoring

4. Remove Grafana left-over files by executing the following command:

   # apt-get remove grafana && rm -rf /usr/share/grafana /etc/grafana /var/lib/grafana

5. Reinstall both extensions in this order:

   # plesk bin extension --install grafana
   # plesk bin extension --install monitoring