Enable AWS CloudFormation Stack Notifications

01 Sign in to the AWS Management Console.

02 Navigate to CloudFormation dashboard at http://console.aws.amazon.com/cloudformation/.

03 Use the Filter dropdown menu to list all the active stacks available in the current AWS region.

04 Select a CloudFormation stack that you want to examine.

05 Click the Action dropdown menu from the dashboard top menu and select Update Stack:

to access the stack configuration page.

06 Click the Next button until you reach the Options page.

07 In the Advanced section, under Notification options, perform one of the following actions:

cloudformation-new-sns-topic
1. Select New Amazon SNS topic: to create a new SNS topic and subscribe to it using your email address. In the Topic box enter a name for the new SNS topic and in the Email box enter the email address where you want to receive notifications, as soon as changes are made to the selected stack.
2. Select Existing Amazon SNS topic and choose a pre-existing SNS topic from the dropdown list: .
3. Select Existing topic ARN and type the Amazon Resource Name (ARN) of an existing SNS topic, e.g. arn:aws:sns:us-east-1:123456789012:MyCFSNSTopic.

08 Click Next and review the new configuration for the selected stack.

09 Click Update to apply the changes. Once the stack status is changed to UPDATE_COMPLETE, the integration with the selected SNS topic is complete.

10 If you chose to create a new SNS topic (step no. 8 a.), use your email client application and open the message from AWS Notifications, then click on the appropriate link to confirm your subscription.

11 Repeat steps no. 4 – 10 to integrate AWS SNS with other CloudFormation stacks available in the selected region.

12 Change the AWS region from the navigation bar to repeat the process for the other regions.

To associate a Simple Notification Service (SNS) topic with the selected CloudFormation stack you need to get first the SNS topic ARN. If you need to create a new SNS topic follow the next step. To use an existing topic, just go to step no. 2.'

01 Create a new SNS topic for integration with the selected CloudFormation stack:

1. Run create-topic command (OSX/Linux/UNIX) to create a new SNS topic for sending email notifications:
   aws sns create-topic
   	--region us-east-1
   	--name MyCFSNSTopic
   

2. The command output should return the new SNS topic ARN:
   
   {
       "TopicArn": "arn:aws:sns:us-east-1:123456789012:MyCFSNSTopic"
   }
   

3. Run subscribe command (OSX/Linux/UNIX) to send the subscription confirmation message to the notification-endpoint (i.e. your email address):
   
   aws sns subscribe
   	--topic-arn arn:aws:sns:us-east-1:123456789012:MyCFSNSTopic
   	--protocol email
   	--notification-endpoint user@domain.com
   

4. Run confirm-subscription command (OSX/Linux/UNIX) to confirm the subscription by validating the token sent to the notification endpoint selected (the command does not return an output):
   
   aws sns confirm-subscription
   	--topic-arn arn:aws:sns:us-east-1:123456789012:MyCFSNSTopic
   	--token 2035092f37fb687f5d51e6e241d7700ae02f7124d8268910b858cb4db727ceeb2474bb937929d3bdd7ce5d0cce19325d036bc858d3c217426bcafa9c501a2cace93b83f1dd3797627467553dc438a8c974119496fc3eff026eaa5d14472ded6f9a5c43aec62d83ef5f49109da718e14
   

02 Run list-topics command (OSX/Linux/UNIX) to list the ARN of each SNS topic available in the selected AWS region:

aws sns list-topics
	--region us-east-1

03The command output should return the requested ARN(s):

{
    "Topics": [
        {
            "TopicArn": "arn:aws:sns:us-east-1:123456789012:CFNotifyMe"
        },
        {
            "TopicArn": "arn:aws:sns:us-east-1:123456789012:MySNSTopic"
        }

    ]
}

04Run update-stack command (OSX/Linux/UNIX) to update the selected CloudFormation stack and associate it with the specified SNS topic by using the topic ARN as identifier:

aws cloudformation update-stack
	--stack-name MyWebProdStack
	--use-previous-template
	--notification-arns "arn:aws:sns:us-east-1:123456789012:CFNotifyMe"

05The command output should return the ID of the updated stack:

{
    "StackId": "arn:aws:cloudformation:us-east-1:123456789012:stack/
                MyWebProdStack/f1f44d40-65e3-11e6-a140-503f23fb55fe"
}

06 Repeat step no. 4 and 5 to integrate AWS SNS with other CloudFormation stacks available in the selected region.

07 Change the AWS region to repeat the process for the other regions.