Create a CloudWatch alarm for an instance

You can create a CloudWatch alarm that monitors CloudWatch metrics for one of your instances. CloudWatch will automatically send you a notification when the metric reaches a threshold you specify. You can create a CloudWatch alarm using the Amazon EC2 console, or using the more advanced options provided by the CloudWatch console.

To create an alarm using the CloudWatch console

For examples, see Creating Amazon CloudWatch Alarms in the Amazon CloudWatch User Guide.

New console

To create an alarm using the Amazon EC2 console

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

2. In the navigation pane, choose Instances.

3. Select the instance and choose Actions, Monitoring, Manage CloudWatch alarms.

4. On the Manage CloudWatch alarms detail page, under Add or edit alarm, select Create a new alarm.

5. For Alarm notification, choose whether to turn the toggle on or off to configure Amazon Simple Notification Service (Amazon SNS) notifications. Enter an existing Amazon SNS topic or enter a name to create a new topic.

6. For Alarm action, choose whether to turn the toggle on or off to specify an action to take when the alarm is triggered. Select an action from the dropdown.

7. For Alarm thresholds, select the metric and criteria for the alarm. For example, you can leave the default settings for Group samples by (Average) and Type of data to sample (CPU utilization). For Alarm when, choose >= and enter 0.80. For Consecutive period, enter 1. For Period, select 5 minutes.

8. (Optional) For Sample metric data, choose Add to dashboard.

9. Choose Create.

Old console

To create an alarm using the Amazon EC2 console

1. Open the Amazon EC2 console at https://console.aws.amazon.com/ec2/.

2. In the navigation pane, choose Instances.

3. Select the instance.

4. On the Monitoring tab located at the bottom of the page, choose Create Alarm. Or, from the Actions dropdown, choose CloudWatch Monitoring, Add/Edit Alarm.

5. In the Create Alarm dialog box, do the following:

   1. Choose create topic. For Send a notification to, enter a name for the SNS topic. For With these recipients, enter one or more email addresses to receive notification.

   2. Specify the metric and the criteria for the policy. For example, you can leave the default settings for Whenever (Average of CPU Utilization). For Is, choose >= and enter 80 percent. For For at least, enter 1 consecutive period of 5 Minutes.

   3. Choose Create Alarm.