# CreateSubdomain
Creates a Lightsail subdomain, such as `mysite`, with the web address `mysite.amazonlightsail.com`. After the subdomain is created, use the `UpdateSubdomainAssociation` action to associate it with a Lightsail resource.
When you create a nested subdomain, such as `blog.mysite`, and you don't already have the top-level subdomain (`mysite`), Lightsail adds the top-level subdomain to your account in the `IMPLICIT` state.
You can have up to 30 subdomains in your account. Nested subdomains, subdomains in the `CREATE_FAILED` state, and deleted subdomains that other accounts can't create yet count toward this quota. Subdomains in the `IMPLICIT` state don't count toward this quota.
## Request Syntax
```
{
"subdomainName": "{{string}}",
"tags": [
{
"key": "{{string}}",
"value": "{{string}}"
}
]
}
```
## Request Parameters
For information about the parameters that are common to all actions, see [Common Parameters](CommonParameters.md).
The request accepts the following data in JSON format.
** [subdomainName](#API_CreateSubdomain_RequestSyntax) **
The subdomain to create (for example, `mysite` or `blog.mysite`).
A subdomain can contain one or two labels separated by a period (`.`). Each label must start and end with a lowercase letter or a number, and can contain only lowercase letters, numbers, and hyphens (`-`). The name can be up to 39 characters long, including periods. Labels that start with `xn--` aren't supported, and some names are reserved.
Specify only the subdomain. A web address, such as `mysite.amazonlightsail.com`, isn't accepted.
To create a nested subdomain, you must own the top-level subdomain or be able to create it.
Type: String
Required: Yes
** [tags](#API_CreateSubdomain_RequestSyntax) **
The tag keys and optional values to add to the subdomain during create.
Use the `TagResource` action to tag a resource after it's created.
Type: Array of [Tag](API_Tag.md) objects
Required: No
## Response Syntax
```
{
"operation": {
"createdAt": number,
"errorCode": "string",
"errorDetails": "string",
"id": "string",
"isTerminal": boolean,
"location": {
"availabilityZone": "string",
"regionName": "string"
},
"operationDetails": "string",
"operationType": "string",
"resourceName": "string",
"resourceType": "string",
"status": "string",
"statusChangedAt": number
},
"subdomain": {
"arn": "string",
"attachedResource": {
"arn": "string",
"attachedAt": number,
"name": "string"
},
"attachingResource": {
"arn": "string",
"attachedAt": number,
"name": "string"
},
"children": [
"Subdomain"
],
"createdAt": number,
"depth": number,
"fqdn": "string",
"location": {
"availabilityZone": "string",
"regionName": "string"
},
"parentFqdn": "string",
"state": "string",
"subdomainName": "string",
"tags": [
{
"key": "string",
"value": "string"
}
]
}
}
```
## Response Elements
If the action is successful, the service sends back an HTTP 200 response.
The following data is returned in JSON format by the service.
** [operation](#API_CreateSubdomain_ResponseSyntax) **
An object that describes the result of the action, such as the status of the request, the timestamp of the request, and the resources affected by the request.
Type: [Operation](API_Operation.md) object
** [subdomain](#API_CreateSubdomain_ResponseSyntax) **
An object that describes the subdomain that was created.
Type: [Subdomain](API_Subdomain.md) object
## Errors
For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).
** AccessDeniedException **
Lightsail throws this exception when the user cannot be authenticated or uses invalid credentials to access a resource.
HTTP Status Code: 400
** InvalidInputException **
Lightsail throws this exception when user input does not conform to the validation rules of an input field.
Domain and distribution APIs are only available in the N. Virginia (`us-east-1`) AWS Region. Please set your AWS Region configuration to `us-east-1` to create, view, or edit these resources.
HTTP Status Code: 400
** NotFoundException **
Lightsail throws this exception when it cannot find a resource.
HTTP Status Code: 400
** OperationFailureException **
Lightsail throws this exception when an operation fails to execute.
HTTP Status Code: 400
** ServiceException **
A general service exception.
HTTP Status Code: 500
** UnauthenticatedException **
Lightsail throws this exception when the user has not been authenticated.
HTTP Status Code: 400
## See Also
For more information about using this API in one of the language-specific AWS SDKs, see the following:
+ [AWS Command Line Interface V2](https://docs.aws.amazon.com/goto/cli2/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for C\+\+](https://docs.aws.amazon.com/goto/SdkForCpp/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for Python (Boto3)](https://docs.aws.amazon.com/goto/boto3/lightsail-2016-11-28/CreateSubdomain)
+ [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/lightsail-2016-11-28/CreateSubdomain)