How to Create CloudFormation Stack using Change Sets – Part 7

To preview how a AWS CloudFormation stack will be configured before creating the stack, create a change set. This functionality allows you to examine various configurations and make corrections and changes to your stack before executing the change set.

Creating a Change Set for a New Stack

To create a change set for a new stack, submit the configuration that you want to use by providing a template, input parameter values, or both.

To create a change set (console)

1. In the AWS CloudFormation console, choose Create Stack, and then choose Create Change Set for New Stack.

• On the Select Template page, specify the location of your template.
• For a template stored locally, choose Upload a template to Amazon S3. Choose File to navigate to the file, choose the file, and then choose Next.
• For a template stored in an Amazon S3 bucket, choose Specify an Amazon S3 URL. Type or paste the URL for the template, and then choose Next.

If your template is stored in a versioning-enabled bucket, you can specify a specific version, for example: https://s3.amazonaws.com/templates/myTemplate.template?versionId=123ab1cdeKdOW5IH4GAcYbEngcpTJTDW

For more information, see Managing Objects in a Versioning-Enabled Bucket in the Amazon Simple Storage Service Console User Guide.

• On the Specify Details page, configure the following items:
• Type the Stack name.
• (Optional) To identify your change set, type its Name and Description.
• If your template contains parameters, type the parameter values in the Parameters section.

When you finish, choose Next.

• (Optional) On the Options page, update the stack’s service role, the stack tags, and the stack’s Amazon SNS notification topic, and then choose Next.
• On the Review page, review the proposed configuration.

If the template includes AWS Identity and Access Management (IAM) resources, select I acknowledge that this template may create IAM resources to acknowledge that AWS CloudFormation might create IAM resources if you execute this change set. IAM resources can modify permissions in your AWS account. Review these resources to ensure that you allow the correction actions. For more information, see Controlling Access with AWS Identity and Access Management.

When you finish, choose Create change set.

While AWS CloudFormation begins to create the change set, the status of the change set is CREATE_IN_PROGRESS. When AWS CloudFormation completes the creation progress, it sets its status to CREATE_COMPLETE. In the Changes section, AWS CloudFormation lists the proposed configuration of your stack.

If AWS CloudFormation fails to create the change set and reports the CREATE_FAILED status, fix the error displayed in the Status field, and then create a new change set. At this stage, you can try various configurations and make corrections and changes to your stack before executing the next change set.

• To create a new stack using the change set, choose Execute, and then choose Execute again.

When you create a change set, AWS CloudFormation launches a stack and reports the REVIEW_IN_PROGRESS status until you execute the change set.