This is the new *CloudFormation Template Reference Guide*. Please update your bookmarks and links. For help getting started with CloudFormation, see the [AWS CloudFormation User Guide](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/Welcome.html).

# AWS::EC2::NetworkInterfaceAttachment
<a name="aws-resource-ec2-networkinterfaceattachment"></a>

Attaches an elastic network interface (ENI) to an Amazon EC2 instance. You can use this resource type to attach additional network interfaces to an instance without interruption.

## Syntax
<a name="aws-resource-ec2-networkinterfaceattachment-syntax"></a>

To declare this entity in your CloudFormation template, use the following syntax:

### JSON
<a name="aws-resource-ec2-networkinterfaceattachment-syntax.json"></a>

```
{
  "Type" : "AWS::EC2::NetworkInterfaceAttachment",
  "Properties" : {
      "[DeleteOnTermination](#cfn-ec2-networkinterfaceattachment-deleteontermination)" : Boolean,
      "[DeviceIndex](#cfn-ec2-networkinterfaceattachment-deviceindex)" : String,
      "[EnaQueueCount](#cfn-ec2-networkinterfaceattachment-enaqueuecount)" : Integer,
      "[EnaSrdSpecification](#cfn-ec2-networkinterfaceattachment-enasrdspecification)" : EnaSrdSpecification,
      "[InstanceId](#cfn-ec2-networkinterfaceattachment-instanceid)" : String,
      "[NetworkInterfaceId](#cfn-ec2-networkinterfaceattachment-networkinterfaceid)" : String
    }
}
```

### YAML
<a name="aws-resource-ec2-networkinterfaceattachment-syntax.yaml"></a>

```
Type: AWS::EC2::NetworkInterfaceAttachment
Properties:
  [DeleteOnTermination](#cfn-ec2-networkinterfaceattachment-deleteontermination): Boolean
  [DeviceIndex](#cfn-ec2-networkinterfaceattachment-deviceindex): String
  [EnaQueueCount](#cfn-ec2-networkinterfaceattachment-enaqueuecount): Integer
  [EnaSrdSpecification](#cfn-ec2-networkinterfaceattachment-enasrdspecification): 
    EnaSrdSpecification
  [InstanceId](#cfn-ec2-networkinterfaceattachment-instanceid): String
  [NetworkInterfaceId](#cfn-ec2-networkinterfaceattachment-networkinterfaceid): String
```

## Properties
<a name="aws-resource-ec2-networkinterfaceattachment-properties"></a>

`DeleteOnTermination`  <a name="cfn-ec2-networkinterfaceattachment-deleteontermination"></a>
Whether to delete the network interface when the instance terminates. By default, this value is set to `true`.  
*Required*: No  
*Type*: Boolean  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`DeviceIndex`  <a name="cfn-ec2-networkinterfaceattachment-deviceindex"></a>
The network interface's position in the attachment order. For example, the first attached network interface has a `DeviceIndex` of 0.  
*Required*: Yes  
*Type*: String  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

`EnaQueueCount`  <a name="cfn-ec2-networkinterfaceattachment-enaqueuecount"></a>
The number of ENA queues created with the instance.  
*Required*: No  
*Type*: Integer  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`EnaSrdSpecification`  <a name="cfn-ec2-networkinterfaceattachment-enasrdspecification"></a>
Configures ENA Express for the network interface that this action attaches to the instance.  
*Required*: No  
*Type*: [EnaSrdSpecification](aws-properties-ec2-networkinterfaceattachment-enasrdspecification.md)  
*Update requires*: [No interruption](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-no-interrupt)

`InstanceId`  <a name="cfn-ec2-networkinterfaceattachment-instanceid"></a>
The ID of the instance to which you will attach the ENI.  
*Required*: Yes  
*Type*: String  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

`NetworkInterfaceId`  <a name="cfn-ec2-networkinterfaceattachment-networkinterfaceid"></a>
The ID of the ENI that you want to attach.  
*Required*: Yes  
*Type*: String  
*Update requires*: [Replacement](https://docs.aws.amazon.com/AWSCloudFormation/latest/UserGuide/using-cfn-updating-stacks-update-behaviors.html#update-replacement)

## Return values
<a name="aws-resource-ec2-networkinterfaceattachment-return-values"></a>

### Ref
<a name="aws-resource-ec2-networkinterfaceattachment-return-values-ref"></a>

When you pass the logical ID of this resource to the intrinsic `Ref` function, `Ref` returns the resource name.

For more information about using the `Ref` function, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-ref.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-ref.html).

### Fn::GetAtt
<a name="aws-resource-ec2-networkinterfaceattachment-return-values-fn--getatt"></a>

The `Fn::GetAtt` intrinsic function returns a value for a specified attribute of this type. The following are the available attributes and sample return values.

For more information about using the `Fn::GetAtt` intrinsic function, see [https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html](https://docs.aws.amazon.com/AWSCloudFormation/latest/TemplateReference/intrinsic-function-reference-getatt.html).

#### 
<a name="aws-resource-ec2-networkinterfaceattachment-return-values-fn--getatt-fn--getatt"></a>

`AttachmentId`  <a name="AttachmentId-fn::getatt"></a>
The ID of the network interface attachment.

## Examples
<a name="aws-resource-ec2-networkinterfaceattachment--examples"></a>



### Network interface attachment
<a name="aws-resource-ec2-networkinterfaceattachment--examples--Network_interface_attachment"></a>

The following example attaches `MyNetworkInterface` to `MyInstance`.

#### JSON
<a name="aws-resource-ec2-networkinterfaceattachment--examples--Network_interface_attachment--json"></a>

```
"NetworkInterfaceAttachment" : {
   "Type" : "AWS::EC2::NetworkInterfaceAttachment",
      "Properties" : {
         "InstanceId" : {"Ref" : "MyInstance"},
         "NetworkInterfaceId" : {"Ref" : "MyNetworkInterface"},
         "DeviceIndex" : "1" 
      }
}
```

#### YAML
<a name="aws-resource-ec2-networkinterfaceattachment--examples--Network_interface_attachment--yaml"></a>

```
NetworkInterfaceAttachment:
   Type: AWS::EC2::NetworkInterfaceAttachment
   Properties:
      InstanceId:
         Ref: MyInstance
      NetworkInterfaceId:
         Ref: MyNetworkInterface
      DeviceIndex: 1
```