Creating a file system Storage Capacity Utilization alarm - FSx for ONTAP
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Creating a file system Storage Capacity Utilization alarm

We recommend that you do not exceed an average SSD storage capacity utilization of 80% in an ongoing basis. Occasional SSD storage utilization spikes above 80% are acceptable. Maintaining an average utilization under 80% provides you with enough capacity to increase your storage without encountering issues. The following procedure shows how to create a CloudWatch alarm that alerts you to when your file system's SSD storage utilization is approaching 80%.

To create a file system SCU alarm

You can use the StorageCapacityUtilization metric to create an alarm that is triggered when one or more of your FSx for ONTAP file systems have reached a storage utilization threshold.

  1. Open the CloudWatch console at

  2. In the left navigation pane, under Alarms, choose All alarms. Then, choose Create alarm. Within the create alarm wizard, choose Select metric.

  3. In the graph explorer, choose the Multi source query tab.

  4. In the query builder, choose the following:

    • For Namespace, select AWS/FSx > Detailed File System Metrics.

    • For Metric name, select MAX(StorageCapacityUtilization).

    • For Filter by, you can optionally include or exclude specific file systems by their ID. If you leave Filter by empty, your alarm will trigger when any of your file systems exceed your alarm’s storage capacity utilization threshold.

    • Leave the rest of the options empty, and choose Graph query.

  5. Choose Select metric. Back in the wizard, in the Metric section, give your metric a Label. We recommend keeping the Period to 5 minutes.

  6. Under Conditions, choose the Static threshold type, whenever your metric is Greater/Equal to 80.

  7. Choose Next to go to the Configure actions page.

To configure alarm actions

You can configure a variety of actions for your alarm to trigger when it reaches the threshold you configure. In this example, we choose a Simple Notification Service (SNS) topic, but you can learn about other actions in Using Amazon CloudWatch alarms in the Amazon CloudWatch User Guide.

  1. In the Notification section, choose an SNS topic to notify when your alarm is in the ALARM state. You can choose an existing topic or create a new one. You will receive a subscription notification that you need to confirm before you’ll receive alarm notifications to the email address.

  2. Choose Next.

To finish the alarm

Follow these instructions to complete the process of creating your CloudWatch alarm.

  1. On the Add name and description page, give your alarm a name, and optionally a description, then choose Next.

  2. Review everything you’ve configured in the Preview and create page, and then choose Create alarm.