{{<figuresrc="/media/docs/alerting/alert-rule-evaluation-2.png"max-width="750px"alt="Set the evaluation behavior of the alert rule in Grafana."caption="Set alert rule evaluation">}}
| **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](#pending-period). |
| **Alerting** | The state of an alert that has breached the threshold for longer than the [pending period](#pending-period). |
| **Recovering** | The state of a firing alert when the threshold is no longer breached, but for less than the [keep firing for](#keep-firing-for) period. |
{{<figuresrc="/media/docs/alerting/alert-rule-evaluation-basic-statediagram.png"alt="A diagram of the lifecyle of a firing alert instance."max-width="750px">}}
If an alert rule changes (except for updates to annotations, the evaluation interval, or other internal fields), its alert instances reset to the **Normal** state, and update accordingly during the next evaluation.
1. When they transition to the **Alerting** state.
2. When they transition to **Normal** state and marked as `Resolved`, either from the **Alerting** or **Recovering** state.
## Evaluation group
Every alert rule and recording rule is assigned to an evaluation group.
Each evaluation group contains an **evaluation interval** that determines how frequently the rule is checked. For instance, the evaluation may occur every `10s`, `30s`, `1m`, `10m`, etc.
Rules can be evaluated concurrently or sequentially. For details, see [How rules are evaluated within a group](ref:evaluation-within-a-group).
When the alert condition is met, the alert instance enters the **Pending** state. It remains in this state until the condition has been continuously true for the entire **Pending period**.
- One alert rule can generate multiple alert instances—one for each series or dimension produced by the rule's query. Alert instances from the same alert rule may be in different states.
- Only alert instances in the **Alerting** and **Normal (Resolved)** state are routed for [notifications](ref:notifications).
Consider an alert rule with an **evaluation interval** set at every 30 seconds and a **pending period** of 90 seconds. The evaluation occurs as follows:
