Signals

You can view triggered signals and its history generated by the Forecaster app from the Alerting app.

Warning / Critical (triggered) Copied

The Forecaster app can trigger either of these signals:

• Forecast signal — when the projected value of an observed metric is greater than or equal to (>=) the specified threshold within the specified horizon. If both warning and critical signal condition are satisfied, a critical signal is generated. Forecast signals are labeled with the forecast category, which can be viewed from the Alerting app.

• Static signal — when the current value of an observed metric is above or equal to (>=) the specified threshold.

Note

The static and forecast signals are independent of each other. The same entity can have both forecast and static signals triggered at the same time.

Cleared Copied

A forecast signal is cleared if it was previously triggered and the projected forecast within the specified duration is below the threshold. A static signal is cleared if it was previous triggered and the current status is now below the specified threshold. If a config is removed, signals triggered from entities that match the removed config will also be cleared.

Illustrative example Copied

Refer to the following thresholds as an example:

• Warning: 80% in 2 hours
• Critical: 90% in 1 hour

The example illustrates the lifecycle of signals triggered on an entity by the Forecaster app.

Instrumentation Copied

The Forecaster app leverages an in-house StatsD client to record metrics regarding its internal state. The following is a complete list of metrics collected by the app: