# Import AWS resources into a CloudFormation stack automatically
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You can now import *named resources* automatically when creating or updating CloudFormation stacks. A *named resource* is one with a custom name. For more information, see [Name type](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/aws-properties-name.html) in the *CloudFormation Template Reference*.

When you initiate auto-import, CloudFormation checks for existing resources that match your template and imports them during deployment. For nested stacks, create the change set from the root stack.

After the import is complete and before performing subsequent stack operations, we recommend running drift detection on imported resources. Drift detection ensures that the template configuration matches the actual configuration. For more information, see [Detect drift on an entire CloudFormation stack](detect-drift-stack.md).

To import a resource, they need to meet the following requirements:
+ The resource must have a static custom name defined in your template. Dynamic names (using \$1Ref or other functions) are not currently supported.
+ The resource must have a `DeletionPolicy` of `Retain` or `RetainExceptOnCreate`.
+ The resource must not already belong to another CloudFormation stack.
+ The resource type must support CloudFormation import operations. For more information, see [Resource type support](resource-import-supported-resources.md).
+ The primary ID for the resource type must be in the template. Primary IDs with read only properties aren't supported. To find out what the primary ID is for a type, look for the `primaryIdentifier` property in the resource schema. For more information on the property, see [primaryIdentifier](https://docs.aws.amazon.com/cloudformation-cli/latest/userguide/resource-type-schema.html#schema-properties-primaryidentifier).

**Example auto-import**  
The following example uses a change set, `CreateChangeSet` to create a stack called `my-stack` based on a template file, `template.yaml`, and imports matching resources automatically.  

```
aws cloudformation create-change-set \
  --stack-name my-stack \
  --change-set-name CreateChangeSet \
  --change-set-type CREATE \
  --template-body file://template.yaml \
  --import-existing-resources
```

## Troubleshooting
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If auto-import fails, do the following to troubleshoot:
+ Verify the resource name in your template matches the name of the resource exactly
+ Verify that the resource isn't already managed by another stack
+ Make sure the resource type supports import operations
+ Verify your template includes all the required properties for the resource type