You have to create one alert rule per connection.

1.) Go to https://console.aws.amazon.com/cloudwatch choose “All alarms” and click on “Create alarm”

2.) In the following wizard Click on “Select metric”

3.) Choose „DX“ on the following screen

4.) Next pick „Connection Metrics“

5.) Select the Connection you want to monitor and proceed with “Select metric”

6.) For the conditions choose „lower“ than „1“ and click on „Next”

7.) If you have never created a alarm before choose “Create a new topic” type in a name for the topic and the Email-address you want to notify in case of an outage and click on “Create topic”

8.) Check the Email-address you have chosen, you should have a mail in the inbox. You have to klick on the “confirm subscription” hyperlink.

9.) To check the status of the Email Endpoint click on “View in SNS Console”, there should be a green checkmark. If this is the case you can close the SNS Console and click on “Next”

10.) Finally choose a name for the Alarm and give it a description if you want to, after clicking “Next” you will se a summary of the configured alarm. Check the values one more time and click on “Create alarm”