Method: instanceGroupManagers.resize

Resizes the managed instance group. If you increase the size, the group creates new instances using the current instance template. If you decrease the size, the group deletes instances. The resize operation is marked DONE when the resize actions are scheduled even if the group has not yet added or deleted any instances. You must separately verify the status of the creating or deleting actions with the listmanagedinstances method.

When resizing down, the instance group arbitrarily chooses the order in which VMs are deleted. The group takes into account some VM attributes when making the selection including:

  • The status of the VM instance.
  • The health of the VM instance.
  • The instance template version the VM is based on.
  • For regional managed instance groups, the location of the VM instance.

This list is subject to change.

If the group is part of a backend service that has enabled connection draining, it can take up to 60 seconds after the connection draining duration has elapsed before the VM instance is removed or deleted.

HTTP request

POST https://compute.googleapis.com/compute/v1/projects/{project}/zones/{zone}/instanceGroupManagers/{resourceId}/resize

The URL uses gRPC Transcoding syntax.

Path parameters

Parameters
project

string

Project ID for this request.
zone

string

The name of the zone where the managed instance group is located.
resourceId

string

The name of the managed instance group.

Authorization requires the following IAM permission on the specified resource instanceGroupManager:

  • compute.instanceGroupManagers.update

Query parameters

Parameters
requestId

string

An optional request ID to identify requests. Specify a unique request ID so that if you must retry your request, the server will know to ignore the request if it has already been completed.

For example, consider a situation where you make an initial request and the request times out. If you make the request again with the same request ID, the server can check if original operation with the same request ID was received, and if so, will ignore the second request. This prevents clients from accidentally creating duplicate commitments.

The request ID must be a valid UUID with the exception that zero UUID is not supported (00000000-0000-0000-0000-000000000000).
size

integer

The number of running instances that the managed instance group should maintain at any given time. The group automatically adds or removes instances to maintain the number of instances specified by this parameter.

Request body

The request body must be empty.

Response body

If successful, the response body contains data with the following structure:

JSON representation 
{
  "id": string,
  "creationTimestamp": string,
  "name": string,
  "zone": string,
  "clientOperationId": string,
  "operationType": string,
  "targetLink": string,
  "targetId": string,
  "status": enum,
  "statusMessage": string,
  "user": string,
  "progress": integer,
  "insertTime": string,
  "startTime": string,
  "endTime": string,
  "error": {
    "errors": [
      {
        "code": string,
        "location": string,
        "message": string
      }
    ]
  },
  "warnings": [
    {
      "code": enum,
      "message": string,
      "data": [
        {
          "key": string,
          "value": string
        }
      ]
    }
  ],
  "httpErrorStatusCode": integer,
  "httpErrorMessage": string,
  "selfLink": string,
  "region": string,
  "description": string,
  "operationGroupId": string,
  "kind": string
}
Fields
id

string (fixed64 format)

[Output Only] The unique identifier for the operation. This identifier is defined by the server.
creationTimestamp

string

[Deprecated] This field is deprecated.
name

string

[Output Only] Name of the operation.
zone

string

[Output Only] The URL of the zone where the operation resides. Only applicable when performing per-zone operations.
clientOperationId

string

[Output Only] The value of requestId if you provided it in the request. Not present otherwise.
operationType

string

[Output Only] The type of operation, such as insert, update, or delete, and so on.
targetId

string (fixed64 format)

[Output Only] The unique target ID, which identifies a specific incarnation of the target resource.
status

enum

[Output Only] The status of the operation, which can be one of the following: PENDING, RUNNING, or DONE.
statusMessage

string

[Output Only] An optional textual description of the current status of the operation.
user

string

[Output Only] User who requested the operation, for example: user@example.com.
progress

integer

[Output Only] An optional progress indicator that ranges from 0 to 100. There is no requirement that this be linear or support any granularity of operations. This should not be used to guess when the operation will be complete. This number should monotonically increase as the operation progresses.
insertTime

string

[Output Only] The time that this operation was requested. This value is in RFC3339 text format.
startTime

string

[Output Only] The time that this operation was started by the server. This value is in RFC3339 text format.
endTime

string

[Output Only] The time that this operation was completed. This value is in RFC3339 text format.
error

object

[Output Only] If errors are generated during processing of the operation, this field will be populated.
error.errors[]

object

[Output Only] The array of errors encountered while processing this operation.
error.errors[].code

string

[Output Only] The error type identifier for this error.
error.errors[].location

string

[Output Only] Indicates the field in the request that caused the error. This property is optional.
error.errors[].message

string

[Output Only] An optional, human-readable error message.
warnings[]

object

[Output Only] If warning messages are generated during processing of the operation, this field will be populated.
warnings[].code

enum

[Output Only] A warning code, if applicable. For example, Compute Engine returns NO_RESULTS_ON_PAGE if there are no results in the response.
warnings[].message

string

[Output Only] A human-readable description of the warning code.
warnings[].data[]

object

[Output Only] Metadata about this warning in key: value format. For example: 

"data": [  {  "key": "scope",  "value": "zones/us-east1-d"  }
warnings[].data[].key

string

[Output Only] A key that provides more detail on the warning being returned. For example, for warnings where there are no results in a list request for a particular zone, this key might be scope and the key value might be the zone name. Other examples might be a key indicating a deprecated resource and a suggested replacement, or a warning about invalid network settings (for example, if an instance attempts to perform IP forwarding but is not enabled for IP forwarding).
warnings[].data[].value

string

[Output Only] A warning data value corresponding to the key.
httpErrorStatusCode

integer

[Output Only] If the operation fails, this field contains the HTTP error status code that was returned. For example, a 404 means the resource was not found.
httpErrorMessage

string

[Output Only] If the operation fails, this field contains the HTTP error message that was returned, such as NOT FOUND.
region

string

[Output Only] The URL of the region where the operation resides. Only applicable when performing regional operations.
description

string

[Output Only] A textual description of the operation, which is set when the operation is created.
operationGroupId

string

[Output Only] An ID that represents a group of operations, such as when a group of operations results from a bulkInsert API request.
kind

string

[Output Only] Type of the resource. Always compute#operation for Operation resources.

Authorization Scopes

Requires one of the following OAuth scopes:

  • https://www.googleapis.com/auth/compute
  • https://www.googleapis.com/auth/cloud-platform

For more information, see the Authentication Overview.