Production check & Production monitor | Drupal.org
Performance monitor module for Drupal 8 : r/drupal
Drupalmonitor | Drupal.org
TUNNELDATA | Drupal
Introduction to monitoring and New Relic | La Drupalera
Drupal Monitoring – Drupal Security | Droptica
Performance Logging and Monitoring: A module to log and monitor performance statistics for Drupal | 2bits.com, Inc. - Drupal and BackDrop CMS Consulting
Super Monitoring | Drupal.org
System Monitor | Drupal.org
UpTime Widget Drupal module to monitor website reliability | Blog Drudesk
Drupal Module - Super Monitoring for your website
Drupal monitoring
Drupal and WordPress monitor | Lumturio
Production check & Production monitor | Drupal.org