ModifyInstancePlacement - Amazon Elastic Compute Cloud


Modifies the placement attributes for a specified instance. You can do the following:

  • Modify the affinity between an instance and a Dedicated Host. When affinity is set to host and the instance is not associated with a specific Dedicated Host, the next time the instance is started, it is automatically associated with the host on which it lands. If the instance is restarted or rebooted, this relationship persists.

  • Change the Dedicated Host with which an instance is associated.

  • Change the instance tenancy of an instance.

  • Move an instance to or from a placement group.

At least one attribute for affinity, host ID, tenancy, or placement group name must be specified in the request. Affinity and tenancy can be modified in the same request.

To modify the host ID, tenancy, placement group, or partition for an instance, the instance must be in the stopped state.

Request Parameters

The following parameters are for this specific action. For more information about required and optional parameters that are common to all actions, see Common Query Parameters.


The affinity setting for the instance. For more information, see Host affinity in the Amazon EC2 User Guide.

Type: String

Valid Values: default | host

Required: No


The Group Id of a placement group. You must specify the Placement Group Group Id to launch an instance in a shared placement group.

Type: String

Required: No


The name of the placement group in which to place the instance. For spread placement groups, the instance must have a tenancy of default. For cluster and partition placement groups, the instance must have a tenancy of default or dedicated.

To remove an instance from a placement group, specify an empty string ("").

Type: String

Required: No


The ID of the Dedicated Host with which to associate the instance.

Type: String

Required: No


The ARN of the host resource group in which to place the instance. The instance must have a tenancy of host to specify this parameter.

Type: String

Required: No


The ID of the instance that you are modifying.

Type: String

Required: Yes


The number of the partition in which to place the instance. Valid only if the placement group strategy is set to partition.

Type: Integer

Required: No


The tenancy for the instance.


For T3 instances, you must launch the instance on a Dedicated Host to use a tenancy of host. You can't change the tenancy from host to dedicated or default. Attempting to make one of these unsupported tenancy changes results in an InvalidRequest error code.

Type: String

Valid Values: default | dedicated | host

Required: No

Response Elements

The following elements are returned by the service.


The ID of the request.

Type: String


Is true if the request succeeds, and an error otherwise.

Type: Boolean


For information about the errors that are common to all actions, see Common client error codes.


Example 1

This example modifies the affinity of instance i-0b33i09 so that it always has affinity with host h-00548908djdsgfs.

Sample Request &Affinity=host &HostId=h-00548908djdsgfs &InstanceId=i-0b33i09 &AUTHPARAMS

Sample Response

<ModifyInstancePlacementResponse xmlns=""> <requestId>d4904fd9-82c2-4ea5-adfe-a9cc3EXAMPLE</requestId> <return>true</item> </ModifyInstancePlacementResponse>

Example 2

This example places instance i-01234567812345678 in the placement group MyPlacementGroup.

Sample Request &InstanceId=i-01234567812345678 &GroupName=MyPlacementGroup &AUTHPARAMS

See Also

For more information about using this API in one of the language-specific AWS SDKs, see the following: