[ aws . ec2 ]

modify-instance-placement

Description

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 launched, 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.

See also: AWS API Documentation

See ‘aws help’ for descriptions of global parameters.

Synopsis

  modify-instance-placement
[--affinity <value>]
[--group-name <value>]
[--host-id <value>]
--instance-id <value>
[--tenancy <value>]
[--partition-number <value>]
[--host-resource-group-arn <value>]
[--cli-input-json | --cli-input-yaml]
[--generate-cli-skeleton <value>]

Options

--affinity (string)

The affinity setting for the instance.

Possible values:

• default

• host

--group-name (string)

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 (“”).

--host-id (string)

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

--instance-id (string)

The ID of the instance that you are modifying.

--tenancy (string)

The tenancy for the instance.

Note

For T3 instances, you can’t change the tenancy from dedicated to host , or from host to dedicated . Attempting to make one of these unsupported tenancy changes results in the InvalidTenancy error code.

Possible values:

• dedicated

• host

--partition-number (integer)

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

--host-resource-group-arn (string)

The ARN of the host resource group in which to place the instance.

--cli-input-json | --cli-input-yaml (string) Reads arguments from the JSON string provided. The JSON string follows the format provided by --generate-cli-skeleton. If other arguments are provided on the command line, those values will override the JSON-provided values. It is not possible to pass arbitrary binary values using a JSON-provided value as the string will be taken literally. This may not be specified along with --cli-input-yaml.

--generate-cli-skeleton (string) Prints a JSON skeleton to standard output without sending an API request. If provided with no value or the value input, prints a sample input JSON that can be used as an argument for --cli-input-json. Similarly, if provided yaml-input it will print a sample input YAML that can be used with --cli-input-yaml. If provided with the value output, it validates the command inputs and returns a sample output JSON for that command.

See ‘aws help’ for descriptions of global parameters.

Examples

Example 1: To remove an instance’s affinity with a Dedicated Host

The following modify-instance-placement example removes an instance’s affinity with a Dedicated Host and enables it to launch on any available Dedicated Host in your account that supports its instance type.

aws ec2 modify-instance-placement \
    --instance-id i-0e6ddf6187EXAMPLE \
    --affinity default

Output:

{
    "Return": true
}

Example 2: To establish affinity between an instance and the specified Dedicated Host

The following modify-instance-placement example establishes a launch relationship between an instance and a Dedicated Host. The instance is only able to run on the specified Dedicated Host.

aws ec2 modify-instance-placement \
    --instance-id i-0e6ddf6187EXAMPLE \
    --affinity host \
    --host-id i-0e6ddf6187EXAMPLE

Output:

{
    "Return": true
}

For more information, see Modifying Instance Tenancy and Affinity in the Amazon Elastic Compute Cloud User Guide for Linux Instances.

Example 3: To move an instance to a placement group

The following modify-instance-placement example moves an instance to a placement group, stop the instance, modify the instance placement, and then restart the instance.

aws ec2 stop-instances \
    --instance-ids i-0123a456700123456

aws ec2 modify-instance-placement \
    --instance-id i-0123a456700123456 \
    --group-name MySpreadGroup

aws ec2 start-instances \
    --instance-ids i-0123a456700123456

For more information, see Changing the Placement Group for an Instance in the Amazon Elastic Compute Cloud Users Guide.

Example 4: To remove an instance from a placement group

The following modify-instance-placement example removes an instance from a placement group by stopping the instance, modifying the instance placement, and then restarting the instance. The following example specifies an empty string (“”) for the placement group name to indicate that the instance is not to be located in a placement group.

Stop the instance:

aws ec2 stop-instances \
    --instance-ids i-0123a456700123456

Modify the placement (Windows Command Prompt, Linux, and macOS):

aws ec2 modify-instance-placement \
    --instance-id i-0123a456700123456 \
    --group-name ""

Modify the placement (Windows PowerShell):

aws ec2 modify-instance-placement `
    --instance-id i-0123a456700123456 `
    --group-name """"

Restart the instance:

aws ec2 start-instances \
    --instance-ids i-0123a456700123456

Output:

{
    "Return": true
}

For more information, see Modifying Instance Tenancy and Affinity in the Amazon Elastic Compute Cloud User Guide for Linux Instances.

Output

Return -> (boolean)

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