State and health of alert rules
The state and health of alert 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 either of the following states:
State | Description |
---|---|
Normal |
None of the time series returned by the evaluation engine is in a |
Pending |
At least one time series returned by the evaluation engine is |
Firing |
At least one time series returned by the evaluation engine is |
NOTE: Alerts will transition first to
pending
and thenfiring
, thus it will take at least two evaluation cycles before an alert is fired.
Alert instance state
An alert instance can be in either 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 alert rule. |
Keep last state
An alert rule can be configured to keep the last state when a NoData
and/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. |
{status}, KeepLast |
The rule would have received another status but was configured to keep the last state of the alert rule. |
Special alerts for NoData
and Error
When evaluation of an alert rule produces state NoData
or Error
, Grafana Alerting will generate alert instances that have the following additional labels:
Label | Description |
---|---|
alertname |
Either |
datasource_uid |
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.