# CreateApplicationStatusCheck
<a name="API_CreateApplicationStatusCheck"></a>

Creates an application status check for monitoring the health of applications running on your instances. You can configure the protocol, port, path, and thresholds for the health check. The following rules apply:
+ You can create a maximum of 50 application status checks per account.
+ Health checks do not start until you associate the check with instances or tags using `AssociateApplicationStatusCheck`.
+ The `Timeout` value must be less than the `Interval` value.
+ The `Path` must start with a forward slash (`/`). Default: `/`.
+ If you do not specify `Aggregation`, it defaults to `included`, which means the check contributes to the instance-level application status.
+ Default values: `Interval` is 60 seconds, `Timeout` is 6 seconds, `FailureThreshold` is 2, `SuccessThreshold` is 5, `StatusCodeMatcher` is `200`, `InitializationGracePeriodSeconds` is 300 seconds.
+ You can tag the application status check during creation. For more information, see [Tag your Amazon EC2 resources](https://docs.amazonaws.cn/AWSEC2/latest/UserGuide/Using_Tags.html).

## Request Parameters
<a name="API_CreateApplicationStatusCheck_RequestParameters"></a>

The following parameters are for this specific action. For more information about required and optional parameters that are common to all actions, see [Common Query Parameters](CommonParameters.md).

 **Aggregation**   
The aggregation setting for the application status check. When set to `included`, the result of this check contributes to the instance-level application status reported by `DescribeApplicationStatus`. When set to `excluded`, the check runs independently and does not affect the instance-level status. Valid values: `included` \| `excluded`.  
Type: String  
Valid Values: `included | excluded`   
Required: No

 **ClientToken**   
Unique, case-sensitive identifier that you provide to ensure the idempotency of the request. For more information, see [Ensuring idempotency](https://docs.amazonaws.cn/AWSEC2/latest/APIReference/Run_Instance_Idempotency.html).  
Type: String  
Required: No

 **DeviceIndex**   
The index of the network device to use for the health check.  
Type: Integer  
Required: No

 **DryRun**   
Checks whether you have the required permissions for the operation, without actually making the request, and provides an error response. If you have the required permissions, the error response is `DryRunOperation`. Otherwise, it is `UnauthorizedOperation`.  
Type: Boolean  
Required: No

 **FailureThreshold**   
The number of consecutive failed health checks before the application status is considered impaired.  
Type: Integer  
Required: No

 **HealthCheckPath.N**   
The health check paths to use for the application status check. Health check paths define the network path from a source subnet to one or more destination subnets for cross-Availability Zone or Availability Zone to Local Zone health checking. If omitted, health checks are performed in the same subnet as the instance.  
Type: Array of [HealthCheckPathRequestObject](API_HealthCheckPathRequestObject.md) objects  
Required: No

 **InitializationGracePeriodSeconds**   
The number of seconds to wait before starting health checks after an instance is launched. Valid values: 1 to 600.  
Type: Integer  
Valid Range: Minimum value of -1. Maximum value of 600.  
Required: No

 **Interval**   
The interval, in seconds, between health checks.  
Type: Integer  
Required: No

 **IpScope**   
The IP scope to use for the health check. Valid values: `private` \| `public`.  
Type: String  
Valid Values: `private`   
Required: No

 **IpVersion**   
The IP version to use for the health check. Valid values: `ipv4`.  
Type: String  
Valid Values: `ipv4 | ipv6`   
Required: No

 **Path**   
The URL path to use for the health check HTTP request (for example, `/health` or `/status`).  
Type: String  
Required: No

 **Port**   
The port to use for the health check. Valid values: 1 to 65535.  
Type: Integer  
Valid Range: Minimum value of 1. Maximum value of 65535.  
Required: Yes

 **Protocol**   
The protocol to use for the health check. Valid values: `http` \| `https`.  
Type: String  
Valid Values: `http | https`   
Required: Yes

 **StatusCodeMatcher**   
The HTTP status codes that indicate a successful health check response.  
Type: String  
Required: No

 **SuccessThreshold**   
The number of consecutive successful health checks before the application status is considered healthy.  
Type: Integer  
Required: No

 **TagSpecification.N**   
The tags to apply to the application status check.  
Type: Array of [TagSpecification](API_TagSpecification.md) objects  
Required: No

 **Timeout**   
The amount of time, in seconds, to wait for a health check response before considering it failed.  
Type: Integer  
Required: No

## Response Elements
<a name="API_CreateApplicationStatusCheck_ResponseElements"></a>

The following elements are returned by the service.

 **applicationStatusCheck**   
Information about the application status check.  
Type: [ApplicationStatusCheckResponseObject](API_ApplicationStatusCheckResponseObject.md) object

 **requestId**   
The ID of the request.  
Type: String

## Errors
<a name="API_CreateApplicationStatusCheck_Errors"></a>

For information about the errors that are common to all actions, see [Common Error Types](CommonErrors.md).

## Examples
<a name="API_CreateApplicationStatusCheck_Examples"></a>

### To create an application status check
<a name="API_CreateApplicationStatusCheck_Example_1"></a>

This example creates an application status check with HTTP protocol on port 80.

#### Sample Request
<a name="API_CreateApplicationStatusCheck_Example_1_Request"></a>

```
https://ec2.amazonaws.com/?Action=CreateApplicationStatusCheck
&Protocol=http
&Port=80
&AUTHPARAMS
```

#### Sample Response
<a name="API_CreateApplicationStatusCheck_Example_1_Response"></a>

```
<CreateApplicationStatusCheckResult xmlns="http://ec2.amazonaws.com/doc/2016-11-15/">
    <requestId>59dbff89-35bd-4eac-99ed-be587EXAMPLE</requestId>
    <applicationStatusCheck>
        <applicationStatusCheckId>asc-0123456789abcdef0</applicationStatusCheckId>
        <protocol>http</protocol>
        <port>80</port>
    </applicationStatusCheck>
</CreateApplicationStatusCheckResult>
```

## See Also
<a name="API_CreateApplicationStatusCheck_SeeAlso"></a>

For more information about using this API in one of the language-specific Amazon SDKs, see the following:
+  [Amazon Command Line Interface V2](https://docs.amazonaws.cn/goto/cli2/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for .NET V4](https://docs.amazonaws.cn/goto/DotNetSDKV4/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for C\+\+](https://docs.amazonaws.cn/goto/SdkForCpp/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for Go v2](https://docs.amazonaws.cn/goto/SdkForGoV2/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for Java V2](https://docs.amazonaws.cn/goto/SdkForJavaV2/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for JavaScript V3](https://docs.amazonaws.cn/goto/SdkForJavaScriptV3/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for Kotlin](https://docs.amazonaws.cn/goto/SdkForKotlin/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for PHP V3](https://docs.amazonaws.cn/goto/SdkForPHPV3/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for Python](https://docs.amazonaws.cn/goto/boto3/ec2-2016-11-15/CreateApplicationStatusCheck) 
+  [Amazon SDK for Ruby V3](https://docs.amazonaws.cn/goto/SdkForRubyV3/ec2-2016-11-15/CreateApplicationStatusCheck)