SOA-C02 Deployment, Provisioning, and Automation Practice Question

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 file has a syntax error.

  Why it's wrong here

  A CloudFormation template syntax error is detected during the UpdateStack API call itself and produces a ValidationError such as 'Template format error: YAML not well-formed' before any stack state transition occurs. Because the reported failure is a stack state issue (ROLLBACK_COMPLETE), not a parsing failure, the template syntax is irrelevant. Furthermore, a syntax error would leave the stack in its previous valid state, not cause it to enter a rollback state.

• ✓

  The stack is in a failed state from a previous operation and must be deleted or rollback continued.

  Why this is correct

  This is the correct answer because the UpdateStack API explicitly rejects any stack whose current status is ROLLBACK_COMPLETE with a ValidationError stating the stack is in that state and cannot be updated. ROLLBACK_COMPLETE is a terminal failed state typically reached after a failed stack creation rolled back all resources, leaving the stack with no usable resources. To recover, you must delete the stack and recreate it, or if the rollback was incomplete, use ContinueUpdateRollback to reach an updatable state.

• ✗

  The parameter values provided are invalid.

  Why it's wrong here

  Invalid parameter values would cause CloudFormation to return a client-side validation error (e.g., 'Parameter 'InstanceType' must be a valid size') during the UpdateStack request itself, without altering the stack's status. The stack would remain in its prior state (e.g., CREATE_COMPLETE), not ROLLBACK_COMPLETE, because parameter validation happens before any resource operations. The error described is specifically about the stack's rollback state, which is independent of parameter validation.

• ✗

  The IAM role specified lacks permissions.

  Why it's wrong here

  An insufficiently privileged IAM service role would generate an AccessDenied or 'not authorized to perform' error from the UpdateStack API, not a stack-state validation error. IAM permission checks occur during the execution of the update—or at the time the service role is passed—but they do not change the stack's status to ROLLBACK_COMPLETE. The error message pointing to a ROLLBACK_COMPLETE state proves the request passed authorization and reached the stack state validation stage.

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