Documentation Grafana Cloud Testing and synthetics Synthetic Monitoring Configure alerts Configure per-check alerts

Configure per-check alerts

Per-check alerts allow you to create check-specific thresholds for common Synthetic Monitoring alert scenarios, including:

• Number of test failures within a time window.
• TLS certificate expiration threshold (HTTP checks only).

Per-check alerts differ from default alert rules in the following ways:

• You can specify thresholds on a check-by-check basis.
• They leverage Grafana-managed alert rules, while default alert rules use data source-managed alert rules.

Enable per-check alerts on a check

To configure per-check alerts on a check:

1. Navigate to Testing & Synthetics > Synthetics > Checks.
2. Click New Check to create a new check or edit a preexisting check from the list.
3. Click on the Alerting section, then click on the Per-check alerts tab.
4. Select the checkbox beside each alert you would like to enable.
5. Specify the trigger conditions for the alert. Refer to Per-check alerts for alert-specific conditions.

Per-check alerts

Failed checks

The failed checks alert lets you define a threshold condition that determines when check execution failures should trigger an alert. The threshold can be defined based on:

• Number of failures: Number of check execution failures in the selected time range.
• Time range: Has to be greater or equal to the check frequency. Supported values are 5m, 10m, 15m, 20m, 30m, 1h.

TLS certificate expiration

The TLS certificate expiration alert lets you define a threshold condition that determines when to trigger an alert for an upcoming certificate expiration for the target under monitoring. The threshold can be defined based on:

• Number of days until expiration.

How per-check alert rules work

Per-check alert rules are composed of two parts:

• A metric associated with the alert type: This is a metric reported as a result of the Synthetic Monitoring check executions. For example probe_ssl_earliest_cert_expiry.
• A metric associated with the threshold: This is a metric that identifies the threshold set by the user for each specific alert type and check combination, and that’s continuously pushed as long as the alert is enabled for the check.

These two parts are evaluated together in the alert rule, where the values of the metric for the alert type is evaluated against the specific threshold value.

Some alert types can be configured for different time ranges, for example the alert for failed checks. In these cases multiple alert rules might be created in Grafana if the alert is enabled for various checks using different time ranges.