Last updated: 2020-03-06 20:26:26

1. API Description

Domain name for API request:

This API (CreateSubnet) is used to create subnets.

  • You must create a VPC before creating a subnet.
  • After the subnet is successfully created, its IP address range cannot be modified. The subnet IP address range must fall within the VPC IP address range. They can be the same if the VPC has only one subnet. We recommend that you keep the subnet IP address range within the VPC IP address range to reserve IP address ranges for other subnets.
  • The subnet mask of the smallest IP address range that can be created is 28 (16 IP addresses), and that of the largest IP address range is 16 (65,536 IP addresses).
  • IP address ranges of different subnets cannot overlap with each other within the same VPC.
  • A subnet is automatically associated with the default route table once created.

A maximum of 100 requests can be initiated per second for this API.

Note: This API supports Finance regions. If the common parameter Region is a Finance region, a domain name with the Finance region needs to be specified, for example:

2. Input Parameters

The following request parameter list only provides API request parameters and some common parameters. For the complete common parameter list, see Common Request Parameters.

Parameter Name Required Type Description
Action Yes String Common parameter. The value used for this API: CreateSubnet.
Version Yes String Common parameter. The value used for this API: 2017-03-12.
Region Yes String Common parameter. For more information, please see the list of regions supported by the product.
VpcId Yes String The ID of the VPC instance to be operated on. You can obtain the parameter value from the VpcId field in the returned result of DescribeVpcs API.
SubnetName Yes String The subnet name. The maximum length is 60 bytes.
CidrBlock Yes String The subnet IP address range. It must be within the VPC IP address range. Subnet IP address ranges cannot overlap with each other within the same VPC.
Zone Yes String The ID of the availability zone in which the subnet resides. You can set up disaster recovery across availability zones by choosing different availability zones for different subnets.

3. Output Parameters

Parameter Name Type Description
Subnet Subnet Subnet object.
RequestId String The unique request ID, which is returned for each request. RequestId is required for locating a problem.

4. Example

Example1 Create Subnets

Input Example
&<common request parameters>

Output Example

  "Response": {
    "RequestID": "354f4ac3-8546-4516-8c8a-69e3ab73aa8a",
    "Subnet": {
      "VpcId": "vpc-m3ul053f",
      "IsDefault": false,
      "SubnetName": "TestSubnet",
      "Zone": "ap-guangzhou-1",
      "SubnetId": "subnet-2qhl25io",
      "CidrBlock": "",
      "TotalIpAddressCount": 253,
      "AvailableIpAddressCount": 253,
      "TagSet": [
          "Key": "city",
          "Value": "shanghai"

5. Developer Resources

API Explorer

This tool allows online call, signature authentication, SDK code generation and quick search of APIs to greatly improve the efficiency of using TencentCloud APIs.


TencentCloud API 3.0 integrates SDKs that support various programming languages to make it easier for you to call APIs.

Command Line Interface

6. Error Code

The following only lists the error codes related to the API business logic. For other error codes, see Common Error Codes.

Error Code Description
InvalidParameter Invalid input parameter.
InvalidParameterValue Invalid parameter value
InvalidParameterValue.LimitExceeded The parameter value exceeds the limit.
InvalidParameterValue.Malformed Invalid input parameter format.
InvalidParameterValue.SubnetConflict Subnet CIDR conflict.
InvalidParameterValue.SubnetRange Invalid subnet CIDR.
LimitExceeded Quota limit is reached.
MissingParameter Parameter missing. A required parameter is missing in the request.
ResourceNotFound The resource does not exist.