Debugging Creation Failure of CloudFormation Stack Resources with Disabled Rollback

Answer - B, C.

The AWS Documentation mentions.

Use the AWS CloudFormation console to view the status of your stack.

In the console, you can view a list of stack events while your stack is being created, updated, or deleted.

From this list, find the failure event and then view the status reason for that event.

For Amazon EC2 issues, you can check the cloud-init and cfn logs as these logs capture processes and command outputs when AWS CloudFormation is setting up the instances.

For more information on CloudFormation Troubleshooting, please visit the below URL:

http://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/troubleshooting.html

When a CloudFormation stack creation fails with disabled rollback, it can be difficult to determine the root cause of the failure. To debug such failures, the following approaches can be used:

A. Use CloudTrail to debug all the API calls sent by the CloudFormation stack. CloudTrail provides a record of API calls made in your AWS account. You can use it to trace the API calls that were made during the stack creation process. You can view the CloudTrail logs to identify which API calls succeeded and which ones failed. This can help you to pinpoint the issue and take corrective actions.

B. Use the AWS CloudFormation console to view the events of your stack. The AWS CloudFormation console provides a detailed view of the events that occur during the creation of a stack. You can use the console to view the events that led to the failure of the stack creation process. You can use this information to identify the root cause of the failure and take corrective actions.

C. For Amazon EC2 issues, view the cloud-init and cfn logs published on the Amazon EC2 instance in the /var/log/ directory. For EC2 instances launched as part of the CloudFormation stack, you can view the logs of the instances to determine any issues that may have occurred during the instance launch. These logs can be found in the /var/log/ directory of the instance. Specifically, the cloud-init logs can provide useful information about the status of the instance and any errors that may have occurred.

D. Use AWS Config to debug all the API calls sent by the CloudFormation stack. AWS Config provides a detailed view of the API calls that were made in your AWS account. You can use AWS Config to trace the API calls that were made during the stack creation process. This can help you to identify the root cause of the failure and take corrective actions.

Therefore, the correct answers are A and B.