+++
title = "Create a Metric Alarms"
weight = 11
+++

A metric alarm watches a single CloudWatch metric or the result of a math expression based on CloudWatch metrics. The alarm performs one or more actions based on the value of the metric or expression relative to a threshold over a number of time periods. The action can be an Amazon EC2 action, an Amazon EC2 Auto Scaling action, or a notification sent to an Amazon SNS topic.

### Creating a Metric Alarm

Go to your [CloudWatch Alarms Console](https://console.aws.amazon.com/cloudwatch/home?#alarmsV2:).

1. Click on **Create Alarm**.
1. Click **Select Metric**.
1. This will take you to the Metrics home page, where you will see all the Namespaces available in the account. Select the `MonitoringApp` namespace

![alarm-1](/images/alarm_1.png?width=60pc)

4. Select `LogGroup, ServiceName, ServiceType, operation` dimension and select the `SuccessfulGetItem` metric we created in the previous exercise.

![alarm-2](/images/alarm_2.png?width=60pc)
![alarm-3](/images/alarm_3.png?width=60pc)

5. Enter the threshold value (**for example, 1**) that you want the metric data to be monitored. Notice that **Static** option is selected by default, which means we will be setting a static value as the threshold to be monitored.

6. Expand **Additional configuration** where you can indicate how many occurences of the breach qualifies for the alarm to be triggered. Set the values to 1 out of 5, which will make the alarm get triggered if there has been 1 breaches in 5 evaluation periods. Notice the message at the top of the graph describing the setting as **This alarm will trigger when the blue line goes above the red line for 1 datapoints within 25 minutes.**

7. Click **Next**.

8. In the **Configure actions** screen, you can set what action you want to take when the alarm changes to different states such as

   - `In alarm`
   - `OK`
   - `Insufficient data`

The available options for actions include, - `Send a notification to an SNS topic` - `Take an Auto scaling action` - `EC2 action` if the metric is from an EC2 instance

9. Select **Create a new topic** to create a new SNS topic to send the notification to and provide your email address.

![alarm-4](/images/alarm_4.png?width=50pc)

10. Name it `my_observability_topic`, fill your `e-mail address` and click **Create topic**.
11. Click **Next**.
12. Name it `My Observability Alarm`.
13. Click **Next**.

![alarm-4](/images/alarm_name.png?width=50pc)

14. Review your settings and click **Create alarm**.
15. Open you e-mail inbox and confirm your SNS topic subscription
    ![alarm-4](/images/alarm_confirm.png?width=50pc)

{{% notice warning %}}
If you don't confirm your e-mail subscription, you will not receive any notification emails for triggered alarms. **Always remember to also check your spam folder**.
{{% /notice %}}