Availability Sets - Convert To Virtual Machine Scale Set

Service:

Compute

API Version:

2026-03-01

Create a new Flexible Virtual Machine Scale Set and migrate all the Virtual Machines in the Availability Set. This does not trigger a downtime on the Virtual Machines.

POST https://management.azure.com/subscriptions/{subscriptionId}/resourceGroups/{resourceGroupName}/providers/Microsoft.Compute/availabilitySets/{availabilitySetName}/convertToVirtualMachineScaleSet?api-version=2026-03-01

URI Parameters

Name	In	Required	Type	Description
availabilitySetName	path	True	string	The name of the availability set.
resourceGroupName	path	True	string minLength: 1 maxLength: 90	The name of the resource group. The name is case insensitive.
subscriptionId	path	True	string minLength: 1	The ID of the target subscription.
api-version	query	True	string minLength: 1	The API version to use for this operation.

Request Body

Name	Type	Description
virtualMachineScaleSetName	string	Specifies information about the Virtual Machine Scale Set that the Availability Set should be converted to.

Responses

Name	Type	Description
202 Accepted		Resource operation accepted. Headers Location: string Retry-After: integer
Other Status Codes	CloudError	An unexpected error response.

Security

azure_auth

Azure Active Directory OAuth2 Flow.

Type: oauth2
Flow: implicit
Authorization URL: https://login.microsoftonline.com/common/oauth2/authorize

Scopes

Name	Description
user_impersonation	impersonate your user account

Examples

AvailabilitySet_ConvertToVirtualMachineScaleSet_Gen

Sample request

HTTP

POST https://management.azure.com/subscriptions/{subscription-id}/resourceGroups/rgcompute/providers/Microsoft.Compute/availabilitySets/myAvailabilitySet/convertToVirtualMachineScaleSet?api-version=2026-03-01

{
  "virtualMachineScaleSetName": "{vmss-name}"
}

Sample response

Status code:

202

Location: https://management.azure.com/subscriptions/{subscriptionId}/providers/Microsoft.Compute/locations/westus/operations/{operationId}&monitor=true&api-version=2025-11-01

Definitions

Name	Description
ApiError	Api error.
ApiErrorBase	Api error base.
CloudError	An error response from the Compute service.
ConvertToVirtualMachineScaleSetInput	Describes the Virtual Machine Scale Set to convert from Availability Set.
InnerError	Inner error details.

ApiError

Object

Api error.

Name	Type	Description
code	string	The error code.
details	ApiErrorBase[]	The Api error details
innererror	InnerError	The Api inner error
message	string	The error message.
target	string	The target of the particular error.

ApiErrorBase

Object

Api error base.

Name	Type	Description
code	string	The error code.
message	string	The error message.
target	string	The target of the particular error.

CloudError

Object

An error response from the Compute service.

Name	Type	Description
error	ApiError	Api error.

ConvertToVirtualMachineScaleSetInput

Object

Describes the Virtual Machine Scale Set to convert from Availability Set.

Name	Type	Description
virtualMachineScaleSetName	string	Specifies information about the Virtual Machine Scale Set that the Availability Set should be converted to.

InnerError

Object

Inner error details.

Name	Type	Description
errordetail	string	The internal error message or exception dump.
exceptiontype	string	The exception type.