End of support notice: On October 7th, 2026, AWS will discontinue support for AWS IoT Greengrass Version 1. After October 7th, 2026, you will no longer be able to access the AWS IoT Greengrass V1 resources. For more information, please visit [Migrate from AWS IoT Greengrass Version 1](https://docs.aws.amazon.com/greengrass/v2/developerguide/migrate-from-v1.html).

# CreateGroupCertificateAuthority
<a name="creategroupcertificateauthority-post"></a>

Creates a CA for the group. If a CA already exists, it rotates the existing CA.

URI: `POST /greengrass/groups/GroupId/certificateauthorities`

Produces: application/json

## CLI:
<a name="creategroupcertificateauthority-post-cli"></a>

```
aws greengrass create-group-certificate-authority \
  --group-id <value> \
  [--amzn-client-token <value>]  \
  [--cli-input-json <value>] \
  [--generate-cli-skeleton]
```

cli-input-json format:

```
{
"GroupId": "string",
"AmznClientToken": "string"
}
```

## Parameters:
<a name="creategroupcertificateauthority-post-params"></a>

[**GroupId**](parameters-groupidparam.md)  
The ID of the Greengrass group.  
where used: path; required: true  
type: string

[**X-Amzn-Client-Token**](parameters-clienttoken.md)  
A client token used to correlate requests and responses.  
where used: header; required: false  
type: string

## Responses:
<a name="creategroupcertificateauthority-post-resp"></a>

**200**  
Success. The response body contains the new, active CA ARN.  
 [ CreateGroupCertificateAuthorityResponse](definitions-creategroupcertificateauthorityresponse.md)   

```
{
"GroupCertificateAuthorityArn": "string"
}
```  
CreateGroupCertificateAuthorityResponse  
type: object  
GroupCertificateAuthorityArn  
The ARN of the group certificate authority.  
type: string

**400**  
Invalid request.  
 [ GeneralError](definitions-generalerror.md)   

```
{
"Message": "string",
"ErrorDetails": [
  {
    "DetailedErrorCode": "string",
    "DetailedErrorMessage": "string"
  }
]
}
```  
GeneralError  
General error information.  
type: object  
required: ["Message"]  
Message  
A message that contains information about the error.  
type: string  
ErrorDetails  
A list of error details.  
type: array  
items: [ErrorDetail](definitions-errordetail.md)  
ErrorDetail  
Details about the error.  
type: object  
DetailedErrorCode  
A detailed error code.  
type: string  
DetailedErrorMessage  
A detailed error message.  
type: string

**500**  
Server error.  
 [ GeneralError](definitions-generalerror.md)   

```
{
"Message": "string",
"ErrorDetails": [
  {
    "DetailedErrorCode": "string",
    "DetailedErrorMessage": "string"
  }
]
}
```  
GeneralError  
General error information.  
type: object  
required: ["Message"]  
Message  
A message that contains information about the error.  
type: string  
ErrorDetails  
A list of error details.  
type: array  
items: [ErrorDetail](definitions-errordetail.md)  
ErrorDetail  
Details about the error.  
type: object  
DetailedErrorCode  
A detailed error code.  
type: string  
DetailedErrorMessage  
A detailed error message.  
type: string