1. Create and edit data source-managed rules for Grafana Mimir and Grafana Loki data sources.
1. View rules from Prometheus data sources when [Manage alerts via Alerting UI](ref:configure-prometheus-data-source-alerting) is enabled. However, you cannot create or edit these rules in Grafana.
1. [Import data source-managed rules](ref:import-to-grafana-rules) from Loki, Mimir, and Prometheus into Grafana-managed rules.
Data source-managed rules are supported for horizontal scalability, but they can introduce more operational complexity than Grafana-managed alert rules.
We recommend using [Grafana-managed alert rules](ref:configure-grafana-managed-rules) whenever possible, as they provide a richer feature set and better integration with the full Grafana Alerting workflow.
{{</admonition>}}
## Comparison with Grafana-managed rules
The table below compares Grafana-managed and data source-managed alert rules.
| Supported data sources | All backend data sources enabling the [`alerting` option](ref:rbac) | Only supports creating rules for Mimir and Loki data sources |
| Mix and match data sources | Yes | No |
| Add [expressions](ref:expression-queries) to transform<wbr/> your data and set [alert conditions](ref:alert-condition) | Yes | No |
| [No data and error states](ref:no-data-error-states) | Yes | No |
| [Stale alert instances](ref:stale-alert-instances) | Yes | No |
| [Images in alert notifications](ref:notification-images) | Yes | No |
| [Role-based access control](ref:rbac) | Yes | No |
| [Alert state history](ref:view-alert-state-history) | Yes | No |
| [Alert version history](ref:view-compare-and-restore-alert-rules-versions) | Yes | No |
| [Terraform provisioning](ref:th-provisioning) | Yes | No |
The following diagram shows the architecture of a Mimir setup that uses data source-managed alert rules.
{{<figuresrc="/media/docs/alerting/mimir-managed-alerting-architecture-v2.png"max-width="750px"alt="Data source-managed alerting architecture based on Grafana Mimir">}}
For more information, refer to the [Mimir Ruler API](/docs/mimir/latest/references/http-api/#ruler) or [Loki Ruler API](/docs/loki/latest/api/#ruler).
- **Mimir** - use the `/prometheus` prefix. The Prometheus data source supports both Grafana Mimir and Prometheus, and Grafana expects that both the [Query API](/docs/mimir/latest/operators-guide/reference-http-api/#querier--query-frontend) and [Ruler API](/docs/mimir/latest/operators-guide/reference-http-api/#ruler) are under the same URL. You cannot provide a separate URL for the Ruler API.
- **Loki** - The `local` rule storage type, default for the Loki data source, supports only viewing of rules. To edit rules, configure one of the other rule storage types.
Note that if you delete an alert resource created in the UI, you can no longer retrieve it.
To backup and manage alert rules, you can [provision alerting resources](ref:shared-provision-alerting-resources) using options such as configuration files, Terraform, or the Alerting API.
Use [alert rule evaluation](ref:alert-rule-evaluation) to determine how frequently an alert rule should be evaluated and how quickly it should change its state.
1. Select a namespace or click **+ New namespace**.
1. Select an evaluation group or click **+ New evaluation group**.
If you are creating a new evaluation group, specify the interval for the group.
The [pending period](ref:pending-period) is the period in which an alert rule can be in breach of the condition until it fires.
Once a condition is met, the alert goes into the **Pending** state. If the condition remains active for the duration specified, the alert transitions to the **Firing** state, else it reverts to the **Normal** state.
Add [labels](ref:alert-rule-labels) to your alert rules to set which [notification policy](ref:notification-policies) should handle your firing alert instances.
All alert rules and instances, irrespective of their labels, match the default notification policy. If there are no nested policies, or no nested policies match the labels in the alert rule or alert instance, then the default notification policy is the matching policy.
1. Add labels if you want to change the way your notifications are routed.
Add custom labels by selecting existing key-value pairs from the drop down, or add new labels by entering the new key or value.
Use [annotations](ref:shared-annotations) to add information to alert messages that can help respond to the alert.
Annotations are included by default in notification messages, and can use text or [templates](ref:shared-alert-rule-template) to display dynamic data from queries.
Grafana provides several optional annotations.
1. Optional: Add a summary.
Short summary of what happened and why.
1. Optional: Add a description.
Description of what the alert rule does.
1. Optional: Add a Runbook URL.
Webpage where you keep your runbook for the alert
1. Optional: Add a custom annotation.
Add any additional information that could help address the alert.
1. Optional: **Link dashboard and panel**.
[Link the alert rule to a panel](ref:shared-link-alert-rules-to-panels) to facilitate alert investigation.
