# ModifyLaunchTemplate
<a name="API_ModifyLaunchTemplate"></a>

Modifies a launch template. You can specify which version of the launch template to set as the default version. When launching an instance, the default version applies when a launch template version is not specified.

## Request Parameters
<a name="API_ModifyLaunchTemplate_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).

 **ClientToken**   
Unique, case-sensitive identifier you provide to ensure the idempotency of the request. If a client token isn't specified, a randomly generated token is used in the request to ensure idempotency.  
For more information, see [Ensuring idempotency](https://docs.aws.amazon.com/AWSEC2/latest/APIReference/Run_Instance_Idempotency.html).  
Constraint: Maximum 128 ASCII characters.  
Type: String  
Required: No

 **DryRun**   
Checks whether you have the required permissions for the action, 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

 **LaunchTemplateId**   
The ID of the launch template.  
You must specify either the launch template ID or the launch template name, but not both.  
Type: String  
Required: No

 **LaunchTemplateName**   
The name of the launch template.  
You must specify either the launch template ID or the launch template name, but not both.  
Type: String  
Length Constraints: Minimum length of 3. Maximum length of 128.  
Pattern: `[a-zA-Z0-9\(\)\.\-/_]+`   
Required: No

 **SetDefaultVersion**   
The version number of the launch template to set as the default version.  
Type: String  
Required: No

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

The following elements are returned by the service.

 **launchTemplate**   
Information about the launch template.  
Type: [LaunchTemplate](API_LaunchTemplate.md) object

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

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

For information about the errors that are common to all actions, see [Common client error codes](errors-overview.md#CommonErrors).

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

### Example
<a name="API_ModifyLaunchTemplate_Example_1"></a>

This example sets version 2 of launch template `lt-0a20c965061f64abc` as the default version.

#### Sample Request
<a name="API_ModifyLaunchTemplate_Example_1_Request"></a>

```
https://ec2.amazonaws.com/?Action=ModifyLaunchTemplate
&LaunchTemplateId=lt-0a20c965061f64abc
&SetDefaultVersion=2
&AUTHPARAMS
```

#### Sample Response
<a name="API_ModifyLaunchTemplate_Example_1_Response"></a>

```
<ModifyLaunchTemplateResponse xmlns="http://ec2.amazonaws.com/doc/2016-11-15/">
    <requestId>5b348ca5-bb13-4106-baf9-14d02example</requestId>
    <launchTemplate>
        <createTime>1970-01-01T00:00:00.000Z</createTime>
        <createdBy>arn:aws:iam::123456789012:root</createdBy>
        <defaultVersionNumber>2</defaultVersionNumber>
        <latestVersionNumber>4</latestVersionNumber>
        <launchTemplateId>lt-0a20c965061f64abc</launchTemplateId>
        <launchTemplateName>MyLaunchTemplate</launchTemplateName>
    </launchTemplate>
</ModifyLaunchTemplateResponse>
```

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

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/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/ec2-2016-11-15/ModifyLaunchTemplate) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/ec2-2016-11-15/ModifyLaunchTemplate)