DeletionPolicy attribute
With the DeletionPolicy attribute you can preserve or (in some cases) backup a resource when its stack is deleted. You specify a DeletionPolicy attribute for each resource that you want to control. If a resource has no DeletionPolicy attribute, AWS CloudFormation deletes the resource by default.
Note that this capability also applies to stack update operations that lead to resources being deleted from stacks. For example, if you remove the resource from the stack template, and then update the stack with the template. This capability does not apply to resources whose physical instance is replaced during stack update operations. For example, if you edit a resource's properties such that AWS CloudFormation replaces that resource during a stack update.
Exception: The default policy is Snapshot
for
AWS::RDS::DBCluster
resources and for AWS::RDS::DBInstance
resources that don't specify the DBClusterIdentifier
property.
To keep a resource when its stack is deleted, specify Retain
for that
resource. You can use retain for any resource. For example, you can retain a nested
stack, Amazon S3
bucket, or EC2 instance so that you can continue to use or modify those resources
after you
delete their stacks.
If you want to modify resources outside of AWS CloudFormation, use a retain policy and then delete the stack. Otherwise, your resources might get out of sync with your AWS CloudFormation template and cause stack errors.
For resources that support snapshots, such as AWS::EC2::Volume
, specify
Snapshot
to have AWS CloudFormation create a snapshot before deleting the resource.
The following snippet contains an Amazon S3 bucket resource with a Retain
deletion
policy. When this stack is deleted, AWS CloudFormation leaves the bucket without deleting
it.
JSON
{ "AWSTemplateFormatVersion" : "2010-09-09", "Resources" : { "myS3Bucket" : { "Type" : "AWS::S3::Bucket", "DeletionPolicy" : "Retain" } } }
YAML
AWSTemplateFormatVersion: '2010-09-09' Resources: myS3Bucket: Type: AWS::S3::Bucket DeletionPolicy: Retain
DeletionPolicy options
- Delete
-
AWS CloudFormation deletes the resource and all its content if applicable during stack deletion. You can add this deletion policy to any resource type. By default, if you don't specify a DeletionPolicy, AWS CloudFormation deletes your resources. However, be aware of the following considerations:
-
For
AWS::RDS::DBCluster
resources, the default policy isSnapshot
. -
For
AWS::RDS::DBInstance
resources that don't specify theDBClusterIdentifier
property, the default policy isSnapshot
. -
For Amazon S3 buckets, you must delete all objects in the bucket for deletion to succeed.
-
- Retain
-
AWS CloudFormation keeps the resource without deleting the resource or its contents when its stack is deleted. You can add this deletion policy to any resource type. Note that when AWS CloudFormation completes the stack deletion, the stack will be in
Delete_Complete
state; however, resources that are retained continue to exist and continue to incur applicable charges until you delete those resources.For update operations, the following considerations apply:
-
If a resource is deleted, the DeletionPolicy retains the physical resource but ensures that it's deleted from AWS CloudFormation's scope.
-
If a resource is updated such that a new physical resource is created to replace the old resource, then the old resource is completely deleted, including from AWS CloudFormation's scope.
-
- Snapshot
-
For resources that support snapshots, AWS CloudFormation creates a snapshot for the resource before deleting it. Note that when AWS CloudFormation completes the stack deletion, the stack will be in the
Delete_Complete
state; however, the snapshots that are created with this policy continue to exist and continue to incur applicable charges until you delete those snapshots.Resources that support snapshots include: