# Monitor Flow on Helios with Alerts

Flow alerting in SingleStore Helios monitors the health and activity of Flow instances associated with a cluster. Flow-specific trigger conditions are configured on the Alerts page for a cluster, where severity levels, thresholds, and email subscribers for each alert can be set.

When Flow alerts are enabled for a cluster, the configured alert rules apply to all Flow instances mapped to that cluster. When a rule's threshold is met for any Flow instance, Helios sends email notifications to the cluster's alert subscribers.

The Flow-specific trigger conditions are:

* **Flow CPU Utilization:** Triggers an alert when CPU usage for at least one instance is above a configured threshold for a specified duration.
* **Flow Memory Utilization**: Triggers an alert when memory usage for a Flow instance is above a configured threshold for a specified duration.
* **Flow Inactivity**: Triggers an alert when a Flow instance has not moved any records for a configured period of time.
* **Flow Scheduler Error**: Triggers an alert when the scheduler for a Flow instance enters an error state.

For general alerting concepts (severity levels, thresholds, and subscribers), refer to [Alerts](https://docs.singlestore.com/db/v9.1/user-and-cluster-administration/cluster-health-and-performance/#alerts.md).

## Prerequisites

* Flow on Helios version 4.3.6 or later.

## Configure Flow Alerts

To configure Flow alert rules for a cluster:

1. In the Cloud Portal, navigate to **Monitoring** > **Alerts**.

2. At the top of the page, select the cluster group that contains your cluster.

3. In the **Alerts Configuration** table, locate the row for your cluster.

4. In the **Actions** column for that cluster, click the Edit icon. This opens the alert configuration, including Flow-related trigger conditions for that cluster.

5. In the **Edit Alert Rules** dialog, scroll to the Flow alert types:

   * Flow CPU Utilization
   * Flow Memory Utilization
   * Flow Inactivity
   * Flow Scheduler Error

6. For each Flow alert type that is required:

   1. Enable it

   2. Configure the severity levels (**Critical**, **Warn**, **Info**) with appropriate thresholds and durations

   3. For Flow Scheduler Error, toggle it on (it functions as an on/off rule)

7. In the **Subscribers** section of the alerts configuration, add or update the list of email addresses that should receive alerts for this cluster. 

8. Click **Save** to apply the alert configuration. 

Once saved, the Flow alert rules are enforced for every Flow instance mapped to the cluster. When a configured condition is met, Helios sends email notifications according to the severity and the existing alerting behavior documented for clusters.

***

Modified at: May 12, 2026

Source: [/db/v9.1/load-data/load-data-with-singlestore-flow-on-helios/monitor-flow-on-helios-with-alerts/](https://docs.singlestore.com/db/v9.1/load-data/load-data-with-singlestore-flow-on-helios/monitor-flow-on-helios-with-alerts/)

(An index of the documentation is available at /llms.txt)