← DVA-C02·Amazon Web Services

DVA-C02 Deployment Practice Question

Exhibit

{
  "AWSTemplateFormatVersion": "2010-09-09",
  "Resources": {
    "MyBucket": {
      "Type": "AWS::S3::Bucket",
      "Properties": {
        "BucketName": "my-app-data-12345"
      }
    }
  }
}

Refer to the exhibit. A developer creates this CloudFormation template and tries to deploy it. The deployment fails with 'CREATE_FAILED' for the S3 bucket resource. What is the most likely cause?

⚠ Common exam trap

Test-takers frequently assume the failure is due to a missing configuration (like versioning or policy) rather than recognizing the global uniqueness constraint as the root cause.

Answer choices

Why each option matters

Answer the question above first, then reveal the full breakdown to understand why each option is right or wrong.

Correct answer & explanation

✓

The bucket name is already taken by another AWS account.

S3 bucket names must be globally unique across all AWS accounts. If the bucket name specified in the template is already in use by another account, CloudFormation will fail with CREATE_FAILED for the S3 bucket resource. This is a fundamental requirement of the S3 service, not a template syntax or configuration issue.

Answer analysis

Option-by-option breakdown

For each option: why learners choose it and why it is or isn't the right answer here.

✗
The template does not enable versioning on the bucket.
Why it's wrong here
AWS S3 bucket versioning is an optional feature designed to keep multiple versions of an object in the same bucket, protecting against accidental deletions or overwrites. While highly recommended for data durability and recovery, its absence in a CloudFormation template will not prevent the successful creation of an S3 bucket. Therefore, this template omission is not a valid reason for deployment failure.
✗
The bucket name must be in all lowercase letters.
Why it's wrong here
AWS S3 bucket names must adhere to specific naming conventions, including being entirely in lowercase letters, not containing underscores, and being between 3 and 63 characters long. The provided bucket name, "myuniquebucket123", already satisfies the requirement of being all lowercase. Consequently, this statement incorrectly identifies a naming convention violation as the cause of the deployment issue.
✓
The bucket name is already taken by another AWS account.
Why this is correct
AWS S3 bucket names must be globally unique across all AWS accounts, not just within a single account or region. If the specified bucket name, "myuniquebucket123", has already been claimed by any other AWS customer worldwide, the CloudFormation stack creation will fail with a "BucketAlreadyOwnedByYou" or "BucketAlreadyExists" error. This global uniqueness constraint is a common reason for S3 bucket creation failures, making this a highly plausible cause.
✗
The template does not specify a bucket policy.
Why it's wrong here
An S3 bucket policy is an optional resource-based policy used to define access permissions for the bucket and its objects. While crucial for controlling access and often implemented for security best practices, a bucket policy is not a mandatory component for the initial successful creation of an S3 bucket via CloudFormation. Therefore, the absence of a bucket policy in the template would not cause the stack deployment to fail.

Quick reference

AWS S3 Storage Class Comparison

Storage Class	Min Duration	Retrieval	Use Case
S3 Standard	None	Immediate	Frequently accessed data
S3 Standard-IA	30 days	Immediate	Infrequent access, rapid retrieval
S3 One Zone-IA	30 days	Immediate	Non-critical infrequent data
S3 Intelligent-Tiering	None	Immediate–hours	Unknown or changing access patterns
S3 Glacier Instant	90 days	Milliseconds	Archive with instant retrieval
S3 Glacier Flexible	90 days	Minutes–hours	Archive, flexible retrieval
S3 Glacier Deep Archive	180 days	Hours	Long-term compliance archive

Go deeper

DVA-C02 Deployment Practice Question

Exhibit

Why each option matters

Option-by-option breakdown

AWS S3 Storage Class Comparison

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