PrometheusErrorSendingAlertsToAnyAlertmanager

Meaning

Prometheus has encountered errors sending alerts to a any Alertmanager.

Impact

All alerts may be lost.

Diagnosis

Check connectivity issues between Prometheus and AlertManager cluster. Check NetworkPolicies, network saturation. Check if AlertManager is not overloaded or has not enough resources.

Mitigation

Set multiple AlertManager instances, spread them across nodes.