# How to Set Up Cluster Monitoring Alerts

MongoDB is a source-available cross-platform document-oriented database program for high-volume storage. Classified as a NoSQL database program, MongoDB uses JSON-like documents with optional schemas.

You can set alert policies based on your [cluster performance metrics](https://docs.digitalocean.com/products/databases/mongodb/how-to/monitor-clusters/index.html.md). Alert policies notify you when a performance metric rises above or falls below a threshold you set, and again when a metric returns to within the threshold. You can receive notifications via email or Slack.

## Create an Alert Policy

To create an alert policy, click the name of your database cluster to go its **Overview** page, then click the **Insights** tab.

![The Insights tab of a database cluster](https://docs.digitalocean.com/screenshots/databases/mongodb-insights-tab.291279f7bc5b2e5c5634753b1c4bfd068d300e9ce80030467262b98d7a618d26.png)

Click the **Manage alert policies** button to open the **Manage alert policies window**.

![Creating an alert policy](https://docs.digitalocean.com/screenshots/databases/alert-policy.f042f2c5c616a26c0c17e825cde1dcadde0421f2d7ce6b4f84c1dcb30aa8f619.png)

Fill out the sections in the **Create alert policy** tab to set up an alert:

1. **Specify metric & set threshold**. You need to specify three things in this section:

   - The performance metric that you want to create an alert for, like CPU usage or disk usage.
   - The numerical threshold above or below which the alert condition triggers, like above 70% usage or below 50% usage.
   - The length of time a threshold must be breached before the alert notification triggers, like 5 minutes or 1 day. The performance metric you’re alerting on is averaged over this interval to determine if it violates the threshold.
2. **Select Clusters or tags**. Choose the clusters or tags that you want the alert policy to apply to. You can also choose **All clusters**.
3. **Send alerts via**. Choose at least one method of notification. You can receive notifications via email (the email on your account and the email of any [team members](https://docs.digitalocean.com/platform/teams/index.html.md)) or [Slack](https://slack.com/).

   Slack notifications require Slack authentication. Click **Connect Slack** to authenticate. Once you are authenticated to Slack, you can select any Slack team, direct message group, or individual members to which you have access.
4. **Name and create alert policy**. Give the alert policy a descriptive name, and then click **Create alert policy**.

It may take up to a few minutes for the newly-created alert policy to start evaluating data.

## Manage Alert Policies and Triggered Alerts

From the **Insights** tab, click the **Manage alert policies** button to open the **Manage alert policies** window, then click the **Existing alert policies** tab.

You can see all of your existing alert policies here. If an alert is triggered, it appears in a **Triggered Alerts** section of this tab, and untriggered alerts are under **Alert Policies**.

![Triggered alert policy](https://docs.digitalocean.com/screenshots/databases/alert-firing.ed95582bc8257e7a4d83598e5f394c347632bf2b3fd88cadb9c966b41dddaca9.png)

Click an alert policy’s **More** menu and select **Edit** to modify the alert policy. You can also delete an alert policy from the **More** menu, which permanently removes the alert policy without confirmation.