In this blogpost we try and clear up some confusion by outlining the key differences between commonly confused alerting configuration options: group_interval , group_wait , and repeat_interval . Before digging into these 3 Alertmanager configuration options, let's recap on some Prometheus alerting basics. Prometheus itself has two global clocks: scrape_interval and evaluation_interval . The scrape_interval is the time between each Prometheus scrape (i.e when Prometheus is pulling data from exporters etc.), and the evaluation_interval is the time between each evaluation of Prometheus' alerting rules. When a rule is evaluated, its state can be altered to be either inactive, pending, or firing. Following evaluation, this state is sent to the connected Alertmanager to potentially start/stop the sending of alert notifications. This is where group_by comes into play. In order to avoid continuously sending notifications for similar alerts (like the same pr