AWS::EC2::EIPAssociation

Associates an Elastic IP address with an instance or a network interface. Before you can use an Elastic IP address, you must allocate it to your account. For more information about working with Elastic IP addresses, see Elastic IP address concepts and rules.

An Elastic IP address can be used in EC2-Classic and EC2-VPC accounts. There are differences between an Elastic IP address that you use in a VPC and one that you use in EC2-Classic. For more information, see Differences between instances in EC2-Classic and a VPC.

[EC2-VPC] You must specify AllocationId and either InstanceId, NetworkInterfaceId, or PrivateIpAddress.

[EC2-Classic] You must specify EIP and InstanceId.

Syntax

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

JSON

{ "Type" : "AWS::EC2::EIPAssociation", "Properties" : { "AllocationId" : String, "EIP" : String, "InstanceId" : String, "NetworkInterfaceId" : String, "PrivateIpAddress" : String } }

YAML

Type: AWS::EC2::EIPAssociation Properties: AllocationId: String EIP: String InstanceId: String NetworkInterfaceId: String PrivateIpAddress: String

Properties

AllocationId

[EC2-VPC] The allocation ID. This is required for EC2-VPC.

Required: Conditional

Type: String

Update requires: Some interruptions

EIP

[EC2-Classic] The Elastic IP address to associate with the instance. This is required for EC2-Classic.

Required: Conditional

Type: String

Update requires: Some interruptions

InstanceId

The ID of the instance. The instance must have exactly one attached network interface. For EC2-VPC, you can specify either the instance ID or the network interface ID, but not both. For EC2-Classic, you must specify an instance ID and the instance must be in the running state.

Required: Conditional

Type: String

Update requires: Some interruptions

NetworkInterfaceId

[EC2-VPC] The ID of the network interface. If the instance has more than one network interface, you must specify a network interface ID.

For EC2-VPC, you can specify either the instance ID or the network interface ID, but not both.

Required: Conditional

Type: String

Update requires: Some interruptions

PrivateIpAddress

[EC2-VPC] The primary or secondary private IP address to associate with the Elastic IP address. If no private IP address is specified, the Elastic IP address is associated with the primary private IP address.

Required: No

Type: String

Update requires: No interruption

Return values

Ref

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 Ref.

Examples

Associate an Elastic IP address to an instance

The following example creates an Elastic IP address and a network interface, and associates the Elastic IP address with the network interface. The example uses the ID of an existing subnet and an example IP address from the subnet CIDR range.

JSON

"Resources" : { "myEIP" : { "Type" : "AWS::EC2::EIP", "Properties" : { "Domain" : "vpc" } }, "myENI" : { "Type" : "AWS::EC2::NetworkInterface", "Properties" : { "SubnetId" : "subnet-0231a7e21ca967d2c", "PrivateIpAddress": "10.0.0.16" } }, "eniAssociation" : { "Type" : "AWS::EC2::EIPAssociation", "Properties" : { "AllocationId" : { "Fn::GetAtt" : [ "myEIP", "AllocationId" ] }, "NetworkInterfaceId" : { "Ref" : "myENI" } } } }

YAML

Resources: myEIP: Type: AWS::EC2::EIP Properties: Domain: vpc myENI: Type: AWS::EC2::NetworkInterface Properties: SubnetId: subnet-0231a7e21ca967d2c PrivateIpAddress: 10.0.0.16 eniAssociation: Type: AWS::EC2::EIPAssociation Properties: AllocationId: !GetAtt myEIP.AllocationId NetworkInterfaceId: !Ref myENI