grafana/docs/sources/alerting/fundamentals/alert-rule-evaluation/state-and-health.md

---
aliases:
  - ../../fundamentals/alert-rules/state-and-health/ # /docs/grafana/<GRAFANA_VERSION>/alerting/fundamentals/alert-rules/state-and-health/
  - ../../fundamentals/state-and-health/ # /docs/grafana/<GRAFANA_VERSION>/alerting/fundamentals/state-and-health/
  - ../../unified-alerting/alerting-rules/state-and-health/ # /docs/grafana/<GRAFANA_VERSION>/alerting/unified-alerting/alerting-rules/state-and-health
canonical: https://grafana.com/docs/grafana/latest/alerting/fundamentals/alert-rule-evaluation/state-and-health/
description: Learn about the state and health of alert rules to understand several key status indicators about your alerts
keywords:
  - grafana
  - alerting
  - keep last state
  - guide
  - state
labels:
  products:
    - cloud
    - enterprise
    - oss
title: State and health of alerts
weight: 109
---

# State and health of alerts

There are three key components that help you understand how your alerts behave during their evaluation: [alert instance state](#alert-instance-state), [alert rule state](#alert-rule-state), and [alert rule health](#alert-rule-health). Although related, each component conveys subtly different information.

## Alert instance state

An alert instance can be in either of the following states:

| State        | Description                                                                                 |
| ------------ | ------------------------------------------------------------------------------------------- |
| **Normal**   | The state of an alert when the condition (threshold) is not met.                            |
| **Pending**  | The state of an alert that has breached the threshold but for less than the pending period. |
| **Alerting** | The state of an alert that has breached the threshold for longer than the pending period.   |
| **NoData**   | The state of an alert whose query returns no data or all values are null.                   |
| **Error**    | The state of an alert when an error or timeout occurred evaluating the alert rule.          |

{{< figure src="/media/docs/alerting/alert-instance-states-v3.png" caption="Alert instance state diagram" alt="Alert instance state diagram" max-width="750px" >}}

### Notifications

Alert instances will be routed for [notifications][notifications] when they are in the `Alerting` state or have been `Resolved`, transitioning from `Alerting` to `Normal` state.

{{< figure src="/media/docs/alerting/alert-rule-evaluation-overview-statediagram-v2.png" max-width="750px" >}}

### Keep last state

In the alert rule settings, you can configure to keep the last state of the alert instance when a `NoData` and/or `Error` state is encountered.

The "Keep Last State" option can prevent unintentional alerts from firing, and from resolving and re-firing. Just like normal evaluation, the alert instance transitions from `Pending` to `Alerting` after the pending period has elapsed.

{{< figure src="/media/docs/alerting/alert-rule-configure-no-data-and-error.png" max-width="500px" >}}

### Labels for `NoData` and `Error`

When an alert instance is on the `NoData` or `Error` state, Grafana Alerting includes the following additional labels:

- `alertname`: Either `DatasourceNoData` or `DatasourceError` depending on the state.
- `datasource_uid`: The UID of the data source that caused the state.

You can manage these alerts like regular ones by using their labels to apply actions such as adding a silence, routing via notification policies, and more.

## Alert rule state

The alert rule state is determined by the “worst case” state of the alert instances produced. For example, if one alert instance is `Alerting`, the alert rule state is firing.

An alert rule can be in either of the following states:

| State       | Description                                                                                          |
| ----------- | ---------------------------------------------------------------------------------------------------- |
| **Normal**  | None of the alert instances returned by the evaluation engine is in a `Pending` or `Alerting` state. |
| **Pending** | At least one alert instances returned by the evaluation engine is `Pending`.                         |
| **Firing**  | At least one alert instances returned by the evaluation engine is `Alerting`.                        |

## Alert rule health

An alert rule can have one of the following health statuses:

| State                  | Description                                                                                              |
| ---------------------- | -------------------------------------------------------------------------------------------------------- |
| **Ok**                 | No error when evaluating an alerting rule.                                                               |
| **Error**              | An error occurred when evaluating an alerting rule.                                                      |
| **NoData**             | The absence of data in at least one time series returned during a rule evaluation.                       |
| **{status}, KeepLast** | The rule would have received another status but was configured to keep the last state of the alert rule. |

{{% docs/reference %}}

[notifications]: "/docs/grafana/ -> /docs/grafana/<GRAFANA_VERSION>/alerting/fundamentals/notifications"
[notifications]: "/docs/grafana-cloud/ -> /docs/grafana-cloud/alerting-and-irm/alerting/fundamentals/notifications"

{{% /docs/reference %}}