---
title: "POST /projects/{project}/regions/{region}/instanceGroupManagers/{instanceGroupManager}/startInstances"
method: POST
path: "/projects/{project}/regions/{region}/instanceGroupManagers/{instanceGroupManager}/startInstances"
tags: ["regionInstanceGroupManagers"]
---

# POST /projects/{project}/regions/{region}/instanceGroupManagers/{instanceGroupManager}/startInstances

`POST /projects/{project}/regions/{region}/instanceGroupManagers/{instanceGroupManager}/startInstances`

Flags the specified instances in the managed instance group to be
started. This method increases thetargetSize and decreases the targetStoppedSize
of the managed instance group by the number of instances that you start.
The startInstances operation is marked DONE if
the startInstances request is successful. The underlying
actions take additional time. You must separately verify the status of theSTARTING action with thelistmanagedinstances
method.

In this request, you can only specify instances that are stopped. For
example, if an instance was previously stopped using the stopInstances
method, it can be started using the startInstances method.

If a health check is attached to the managed instance group, the specified
instances will be verified as healthy after they are started.

You can specify a maximum of 1000 instances with this method per request.

## Path parameters

- `project` string, required
- `region` string, required
- `instanceGroupManager` string, required

## Query parameters

- `requestId` string

## Request body

- RegionInstanceGroupManagersStartInstancesRequest
  - `instances` string[] — The URLs of one or more instances to start. This can be a full URL or a partial URL, such as zones/[ZONE]/instances/[INSTANCE_NAME].

## Response `200`

Successful response

---

[API](https://skmtc.net/google/apis/compute.md) · [All operations](https://skmtc.net/google/apis/compute/llms.txt) · [OpenAPI document](https://skmtc-service-staging.skmtc.workers.dev/v1/apis/google/compute/revisions/6120ed8969d4/schema)