Heartbeat monitoring (also known as Cron Job Monitoring) is a great way to monitor servers/computers/devices which are connected to the internet. It is a time-tested method of tracking the health of a device or software system by sending regular heartbeat events to a remote Monitoring Service.
It works in an opposite way compared to the other monitoring types as it requires the monitor to send the requests so that our monitoring system can decide if it is UP or DOWN. Once a monitor has been created, it will be marked with DOWN state, until it receives its first heartbeat event. A heartbeat event can be simply made by making a GET or POST request to the specially generated Heartbeat URL.
The purpose of the Heartbeat monitoring is to know if your scripts, agents, workers, daemons are continuously running as expected. When your monitor is marked as DOWN, you will receive an email notification about this. This allows monitoring of specific scripts and also allows monitoring of any server (via cronjobs/tasks) that is behind a firewall, not allowing incoming traffic to the server.