REST Resource: regionInstanceGroupManagers

Resource: InstanceGroupManager

Represents a Managed Instance Group resource.

An instance group is a collection of VM instances that you can manage as a single entity. For more information, read Instance groups.

For zonal Managed Instance Group, use the instanceGroupManagers resource.

For regional Managed Instance Group, use the regionInstanceGroupManagers resource.

JSON representation 
{
  "id": string,
  "creationTimestamp": string,
  "name": string,
  "description": string,
  "zone": string,
  "region": string,
  "distributionPolicy": {
    "zones": [
      {
        "zone": string
      }
    ]
  },
  "instanceTemplate": string,
  "versions": [
    {
      "name": string,
      "instanceTemplate": string,
      "targetSize": {
        "fixed": integer,
        "percent": integer,
        "calculated": integer
      }
    }
  ],
  "instanceGroup": string,
  "targetPools": [
    string
  ],
  "baseInstanceName": string,
  "fingerprint": string,
  "currentActions": {
    "none": integer,
    "creating": integer,
    "creatingWithoutRetries": integer,
    "verifying": integer,
    "recreating": integer,
    "deleting": integer,
    "abandoning": integer,
    "restarting": integer,
    "refreshing": integer
  },
  "status": {
    "isStable": boolean,
    "versionTarget": {
      "isReached": boolean
    },
    "autoscaler": string
  },
  "targetSize": integer,
  "selfLink": string,
  "autoHealingPolicies": [
    {
      "healthCheck": string,
      "initialDelaySec": integer
    }
  ],
  "updatePolicy": {
    "type": enum,
    "instanceRedistributionType": enum,
    "minimalAction": enum,
    "maxSurge": {
      "fixed": integer,
      "percent": integer,
      "calculated": integer
    },
    "maxUnavailable": {
      "fixed": integer,
      "percent": integer,
      "calculated": integer
    }
  },
  "namedPorts": [
    {
      "name": string,
      "port": integer
    }
  ],
  "kind": string
}
Fields
id

string (fixed64 format)

[Output Only] A unique identifier for this resource type. The server generates this identifier.
creationTimestamp

string

[Output Only] The creation timestamp for this managed instance group in RFC3339 text format.
name

string

The name of the managed instance group. The name must be 1-63 characters long, and comply with RFC1035.
description

string

An optional description of this resource. Provide this property when you create the resource.
zone

string

[Output Only] The URL of the zone where the managed instance group is located (for zonal resources).
region

string

[Output Only] The URL of the region where the managed instance group resides (for regional resources).
distributionPolicy

object

Policy specifying intended distribution of instances in regional managed instance group.
distributionPolicy.zones[]

object

Zones where the regional managed instance group will create and manage instances.
distributionPolicy.zones[].zone

string

The URL of the zone. The zone must exist in the region where the managed instance group is located.
instanceTemplate

string

The URL of the instance template that is specified for this managed instance group. The group uses this template to create all new instances in the managed instance group.
versions[]

object

Specifies the instance templates used by this managed instance group to create instances.

Each version is defined by an instanceTemplate and a name. Every version can appear at most once per instance group. This field overrides the top-level instanceTemplate field. Read more about the relationships between these fields. Exactly one version must leave the targetSize field unset. That version will be applied to all remaining instances. For more information, read about canary updates.
versions[].name

string

Name of the version. Unique among all versions in the scope of this managed instance group.
versions[].instanceTemplate

string

The URL of the instance template that is specified for this managed instance group. The group uses this template to create new instances in the managed instance group until the targetSize for this version is reached.
versions[].targetSize

object

Specifies the intended number of instances to be created from the instanceTemplate. The final number of instances created from the template will be equal to:

  • If expressed as a fixed number, the minimum of either targetSize.fixed or instanceGroupManager.targetSize is used.
  • if expressed as a percent, the targetSize would be (targetSize.percent/100 * InstanceGroupManager.targetSize) If there is a remainder, the number is rounded up.
If unset, this version will update any remaining instances not updated by another version. Read Starting a canary update for more information.
versions[].targetSize.fixed

integer

Specifies a fixed number of VM instances. This must be a positive integer.
versions[].targetSize.percent

integer

Specifies a percentage of instances between 0 to 100%, inclusive. For example, specify 80 for 80%.
versions[].targetSize.calculated

integer

[Output Only] Absolute value of VM instances calculated based on the specific mode.

  • If the value is fixed, then the calculated value is equal to the fixed value.
  • If the value is a percent, then the calculated value is percent/100 * targetSize. For example, the calculated value of a 80% of a managed instance group with 150 instances would be (80/100 * 150) = 120 VM instances. If there is a remainder, the number is rounded up.
instanceGroup

string

[Output Only] The URL of the Instance Group resource.
targetPools[]

string

The URLs for all TargetPool resources to which instances in the instanceGroup field are added. The target pools automatically apply to all of the instances in the managed instance group.
baseInstanceName

string

The base instance name to use for instances in this group. The value must be 1-58 characters long. Instances are named by appending a hyphen and a random four-character string to the base instance name. The base instance name must comply with RFC1035.
fingerprint

string (bytes format)

Fingerprint of this resource. This field may be used in optimistic locking. It will be ignored when inserting an InstanceGroupManager. An up-to-date fingerprint must be provided in order to update the InstanceGroupManager, otherwise the request will fail with error 412 conditionNotMet.

To see the latest fingerprint, make a get() request to retrieve an InstanceGroupManager.

A base64-encoded string.
currentActions

object

[Output Only] The list of instance actions and the number of instances in this managed instance group that are scheduled for each of those actions.
currentActions.none

integer

[Output Only] The number of instances in the managed instance group that are running and have no scheduled actions.
currentActions.creating

integer

[Output Only] The number of instances in the managed instance group that are scheduled to be created or are currently being created. If the group fails to create any of these instances, it tries again until it creates the instance successfully.

If you have disabled creation retries, this field will not be populated; instead, the creatingWithoutRetries field will be populated.
currentActions.creatingWithoutRetries

integer

[Output Only] The number of instances that the managed instance group will attempt to create. The group attempts to create each instance only once. If the group fails to create any of these instances, it decreases the group's targetSize value accordingly.
currentActions.verifying

integer

[Output Only] The number of instances in the managed instance group that are being verified. See the managedInstances[].currentAction property in the listManagedInstances method documentation.
currentActions.recreating

integer

[Output Only] The number of instances in the managed instance group that are scheduled to be recreated or are currently being being recreated. Recreating an instance deletes the existing root persistent disk and creates a new disk from the image that is defined in the instance template.
currentActions.deleting

integer

[Output Only] The number of instances in the managed instance group that are scheduled to be deleted or are currently being deleted.
currentActions.abandoning

integer

[Output Only] The total number of instances in the managed instance group that are scheduled to be abandoned. Abandoning an instance removes it from the managed instance group without deleting it.
currentActions.restarting

integer

[Output Only] The number of instances in the managed instance group that are scheduled to be restarted or are currently being restarted.
currentActions.refreshing

integer

[Output Only] The number of instances in the managed instance group that are being reconfigured with properties that do not require a restart or a recreate action. For example, setting or removing target pools for the instance.
status

object

[Output Only] The status of this managed instance group.
status.isStable

boolean

[Output Only] A bit indicating whether the managed instance group is in a stable state. A stable state means that: none of the instances in the managed instance group is currently undergoing any type of change (for example, creation, restart, or deletion); no future changes are scheduled for instances in the managed instance group; and the managed instance group itself is not being modified.
status.versionTarget

object

[Output Only] A status of consistency of Instances' versions with their target version specified by version field on Instance Group Manager.
status.versionTarget.isReached

boolean

[Output Only] A bit indicating whether version target has been reached in this managed instance group, i.e. all instances are in their target version. Instances' target version are specified by version field on Instance Group Manager.
status.autoscaler

string

[Output Only] The URL of the Autoscaler that targets this instance group manager.
targetSize

integer

The target number of running instances for this managed instance group. You can reduce this number by using the instanceGroupManager deleteInstances or abandonInstances methods. Resizing the group also changes this number.
autoHealingPolicies[]

object

The autohealing policy for this managed instance group. You can specify only one value.
autoHealingPolicies[].healthCheck

string

The URL for the health check that signals autohealing.
autoHealingPolicies[].initialDelaySec

integer

The number of seconds that the managed instance group waits before it applies autohealing policies to new instances or recently recreated instances. This initial delay allows instances to initialize and run their startup scripts before the instance group determines that they are UNHEALTHY. This prevents the managed instance group from recreating its instances prematurely. This value must be from range [0, 3600].
updatePolicy

object

The update policy for this managed instance group.
updatePolicy.type

enum

The type of update process. You can specify either PROACTIVE so that the instance group manager proactively executes actions in order to bring instances to their target versions or OPPORTUNISTIC so that no action is proactively executed but the update will be performed as part of other actions (for example, resizes or recreateInstances calls).
updatePolicy.instanceRedistributionType

enum

The instance redistribution policy for regional managed instance groups. Valid values are:

  • PROACTIVE (default): The group attempts to maintain an even distribution of VM instances across zones in the region.
  • NONE: For non-autoscaled groups, proactive redistribution is disabled.
updatePolicy.minimalAction

enum

Minimal action to be taken on an instance. You can specify either RESTART to restart existing instances or REPLACE to delete and create new instances from the target template. If you specify a RESTART, the Updater will attempt to perform that action only. However, if the Updater determines that the minimal action you specify is not enough to perform the update, it might perform a more disruptive action.
updatePolicy.maxSurge

object

The maximum number of instances that can be created above the specified targetSize during the update process. By default, a fixed value of 1 is used. This value can be either a fixed number or a percentage if the instance group has 10 or more instances. If you set a percentage, the number of instances will be rounded up if necessary.

At least one of either maxSurge or maxUnavailable must be greater than 0. Learn more about maxSurge.
updatePolicy.maxSurge.fixed

integer

Specifies a fixed number of VM instances. This must be a positive integer.
updatePolicy.maxSurge.percent

integer

Specifies a percentage of instances between 0 to 100%, inclusive. For example, specify 80 for 80%.
updatePolicy.maxSurge.calculated

integer

[Output Only] Absolute value of VM instances calculated based on the specific mode.

  • If the value is fixed, then the calculated value is equal to the fixed value.
  • If the value is a percent, then the calculated value is percent/100 * targetSize. For example, the calculated value of a 80% of a managed instance group with 150 instances would be (80/100 * 150) = 120 VM instances. If there is a remainder, the number is rounded up.
updatePolicy.maxUnavailable

object

The maximum number of instances that can be unavailable during the update process. An instance is considered available if all of the following conditions are satisfied:

  • The instance's status is RUNNING.
  • If there is a health check on the instance group, the instance's liveness health check result must be HEALTHY at least once. If there is no health check on the group, then the instance only needs to have a status of RUNNING to be considered available.

By default, a fixed value of 1 is used. This value can be either a fixed number or a percentage if the instance group has 10 or more instances. If you set a percentage, the number of instances will be rounded up if necessary.

At least one of either maxSurge or maxUnavailable must be greater than 0. Learn more about maxUnavailable.
updatePolicy.maxUnavailable.fixed

integer

Specifies a fixed number of VM instances. This must be a positive integer.
updatePolicy.maxUnavailable.percent

integer

Specifies a percentage of instances between 0 to 100%, inclusive. For example, specify 80 for 80%.
updatePolicy.maxUnavailable.calculated

integer

[Output Only] Absolute value of VM instances calculated based on the specific mode.

  • If the value is fixed, then the calculated value is equal to the fixed value.
  • If the value is a percent, then the calculated value is percent/100 * targetSize. For example, the calculated value of a 80% of a managed instance group with 150 instances would be (80/100 * 150) = 120 VM instances. If there is a remainder, the number is rounded up.
namedPorts[]

object

Named ports configured for the Instance Groups complementary to this Instance Group Manager.
namedPorts[].name

string

The name for this named port. The name must be 1-63 characters long, and comply with RFC1035.
namedPorts[].port

integer

The port number, which can be a value between 1 and 65535.
kind

string

[Output Only] The resource type, which is always compute#instanceGroupManager for managed instance groups.

Methods

abandonInstances

 Flags the specified instances to be immediately removed from the managed instance group.

applyUpdatesToInstances

 Apply updates to selected instances the managed instance group.

createInstances

 Creates instances with per-instance configs in this regional managed instance group.

delete

 Deletes the specified managed instance group and all of the instances in that group.

deleteInstances

 Flags the specified instances in the managed instance group to be immediately deleted.

get

 Returns all of the details about the specified managed instance group.

insert

 Creates a managed instance group using the information that you specify in the request.

list

 Retrieves the list of managed instance groups that are contained within the specified region.

listManagedInstances

 Lists the instances in the managed instance group and instances that are scheduled to be created.

patch

 Updates a managed instance group using the information that you specify in the request.

recreateInstances

 Flags the specified instances in the managed instance group to be immediately recreated.

resize

 Changes the intended size of the managed instance group.

setInstanceTemplate

 Sets the instance template to use when creating new instances or recreating instances in this group.

setTargetPools

 Modifies the target pools to which all new instances in this group are assigned.