AWS AWSCloudFormation documentation change
Summary
Added two new troubleshooting sections: 'Pre-deployment validation errors' covering property syntax, resource conflicts, and quota warnings; and 'Express mode completion behavior' explaining resource readiness timing and common issues.
Security assessment
The changes document deployment validation features and express mode behavior without addressing any specific security vulnerability. The validation bypass option could potentially lead to insecure deployments if misused, but there's no evidence of a patched vulnerability or security incident.
Diff
diff --git a/AWSCloudFormation/latest/UserGuide/troubleshooting.md b/AWSCloudFormation/latest/UserGuide/troubleshooting.md index 1f86f1e28..6d9122bee 100644 --- a//AWSCloudFormation/latest/UserGuide/troubleshooting.md +++ b//AWSCloudFormation/latest/UserGuide/troubleshooting.md @@ -7 +7 @@ -Troubleshooting guideTroubleshooting errorsContacting support +Troubleshooting guideTroubleshooting errorsContacting supportPre-deployment validation errorsExpress mode completion behavior @@ -22,0 +23,4 @@ For general questions about CloudFormation, see the [CloudFormation FAQs](https: + * Pre-deployment validation errors + + * Express mode completion behavior + @@ -291,0 +296,58 @@ You can also search for answers and post questions in the [CloudFormation commun +## Pre-deployment validation errors + +Pre-deployment validation catches common errors before CloudFormation provisions resources. When validation fails, the stack operation stops immediately. + +Property syntax validation failed + + +_Cause:_ Your template contains resource property values that don't match the expected schema – for example, an invalid ARN pattern, a type mismatch (string instead of integer), an invalid enum value, or a missing required property. + +_Resolution:_ Review the `ValidationStatusReason` in the event details. It includes the exact property path where the error occurs. Fix the property value in your template and retry the operation. + +Resource name conflict + + +_Cause:_ Your template specifies a resource name that already exists in your account, and the target resource type does not support using an existing resource with that name. + +_Resolution:_ Either change the resource name in your template or remove the existing resource that is causing the conflict. + +Service quota warning + + +_Cause:_ Creating or updating resources would exceed your current AWS service quotas. + +_Resolution:_ Request a quota increase through the Service Quotas console, or modify your template to stay within current limits. + +###### Bypass validation + +If you determine a validation error is a false positive or you need to proceed despite the warning, use the `--disable-validation` AWS CLI flag or set `DisableValidation` to `true` in the API call. + +## Express mode completion behavior + +When you use express mode, stack operations complete as soon as CloudFormation applies the resource configuration. This means that resources might not be fully operational when the stack operation reports success. + +###### Note + +If a resource attribute is referenced in a stack output, CloudFormation waits for the resource to propagate so that it can read the attribute value, even in express mode. + +###### Common issues + +The following issues can occur when you use express mode. + +Resources not yet available + + +Your application might depend on a resource being fully operational immediately after deployment—for example, an Amazon EC2 instance passing health checks or a CloudFront distribution being globally deployed. If so, wait for the resource to reach its final state before relying on it. + +Delete operations still in progress + + +After a stack delete completes in express mode, some resources might not yet be fully removed. If you immediately try to create a new stack with the same resource names, you might encounter name conflicts. + +Dependent resource failures + + +Because express mode doesn't wait for resource stabilization, downstream resources that depend on a previous resource being fully operational might fail. If this occurs, consider using the default deployment mode for that stack. + +For more information about express mode, see [Express mode](./cloudformation-express-mode.html). +