# State and health of alerting rules
<a name="v10-alerting-explore-state"></a>

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This documentation topic is designed for Grafana workspaces that support **Grafana version 10.x**.  
For Grafana workspaces that support Grafana version 12.x, see [Working in Grafana version 12](using-grafana-v12.md).  
For Grafana workspaces that support Grafana version 9.x, see [Working in Grafana version 9](using-grafana-v9.md).  
For Grafana workspaces that support Grafana version 8.x, see [Working in Grafana version 8](using-grafana-v8.md).

The state and health of alerting rules help you understand several key status indicators about your alerts.

There are three key components: *alert rule state*, *alert instance state*, and *alert rule health*. Although related, each component conveys subtly different information.

**Alert rule state**

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


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

**Note**  
Alerts will transition first to `pending` and then `firing`, thus it will take at least two evaluation cycles before an alert is fired.

**Alert instance state**

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


| State | Description | 
| --- | --- | 
| Normal | The state of an alert that is neither firing nor pending, everything is working correctly. | 
| Pending | The state of an alert that has been active for less than the configured threshold duration. | 
| Alerting | The state of an alert that has been active for longer than the configured threshold duration. | 
| NoData | No data has been received for the configured time window. | 
| Error | The error that occurred when attempting to evaluate an alerting rule. | 

**Keep last state**

An alert rule can be configured to keep the last state when `NoData` or `Error` state is encountered. This will both prevent alerts from firing, and from resolving and re-firing. Just like normal evaluation, the alert rule will transition from `Pending` to `Firing` after the pending period has elapsed.

**Alert rule health**

An alert rule can have one 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. | 

**Special alerts for `NoData` and `Error`**

When evaluation of an alerting rule produces state `NoData` or `Error`, Grafana Alerting will generate alert instances that have the following additional labels:


| Label | Description | 
| --- | --- | 
| alertname | Either `DatasourceNoData` or `DatasourceError` depending on the state. | 
| datasource\$1uid | The UID of the data source that caused the state. | 

You can handle these alerts the same way as regular alerts by adding a silence, route to a contact point, and so on.