# RejectNetworkFirewallTransitGatewayAttachment
<a name="API_RejectNetworkFirewallTransitGatewayAttachment"></a>

Rejects a transit gateway attachment request for Network Firewall. When you reject the attachment request, Network Firewall cancels the creation of routing components between the transit gateway and firewall endpoints.

Only the transit gateway owner can reject the attachment. After rejection, no traffic will flow through the firewall endpoints for this attachment.

Use [DescribeFirewall](API_DescribeFirewall.md) to monitor the rejection status. To accept the attachment instead of rejecting it, use [AcceptNetworkFirewallTransitGatewayAttachment](API_AcceptNetworkFirewallTransitGatewayAttachment.md).

**Note**  
Once rejected, you cannot reverse this action. To establish connectivity, you must create a new transit gateway-attached firewall.

## Request Syntax
<a name="API_RejectNetworkFirewallTransitGatewayAttachment_RequestSyntax"></a>

```
{
   "TransitGatewayAttachmentId": "string"
}
```

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

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.

 ** [TransitGatewayAttachmentId](#API_RejectNetworkFirewallTransitGatewayAttachment_RequestSyntax) **   <a name="networkfirewall-RejectNetworkFirewallTransitGatewayAttachment-request-TransitGatewayAttachmentId"></a>
Required. The unique identifier of the transit gateway attachment to reject. This ID is returned in the response when creating a transit gateway-attached firewall.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `^tgw-attach-[0-9a-z]+$`   
Required: Yes

## Response Syntax
<a name="API_RejectNetworkFirewallTransitGatewayAttachment_ResponseSyntax"></a>

```
{
   "TransitGatewayAttachmentId": "string",
   "TransitGatewayAttachmentStatus": "string"
}
```

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

If the action is successful, the service sends back an HTTP 200 response.

The following data is returned in JSON format by the service.

 ** [TransitGatewayAttachmentId](#API_RejectNetworkFirewallTransitGatewayAttachment_ResponseSyntax) **   <a name="networkfirewall-RejectNetworkFirewallTransitGatewayAttachment-response-TransitGatewayAttachmentId"></a>
The unique identifier of the transit gateway attachment that was rejected.  
Type: String  
Length Constraints: Minimum length of 1. Maximum length of 128.  
Pattern: `^tgw-attach-[0-9a-z]+$` 

 ** [TransitGatewayAttachmentStatus](#API_RejectNetworkFirewallTransitGatewayAttachment_ResponseSyntax) **   <a name="networkfirewall-RejectNetworkFirewallTransitGatewayAttachment-response-TransitGatewayAttachmentStatus"></a>
The current status of the transit gateway attachment. Valid values are:  
+  `CREATING` - The attachment is being created
+  `DELETING` - The attachment is being deleted
+  `DELETED` - The attachment has been deleted
+  `FAILED` - The attachment creation has failed and cannot be recovered
+  `ERROR` - The attachment is in an error state that might be recoverable
+  `READY` - The attachment is active and processing traffic
+  `PENDING_ACCEPTANCE` - The attachment is waiting to be accepted
+  `REJECTING` - The attachment is in the process of being rejected
+  `REJECTED` - The attachment has been rejected
For information about troubleshooting endpoint failures, see [Troubleshooting firewall endpoint failures](https://docs.aws.amazon.com/network-firewall/latest/developerguide/firewall-troubleshooting-endpoint-failures.html) in the * AWS Network Firewall Developer Guide*.  
Type: String  
Valid Values: `CREATING | DELETING | DELETED | FAILED | ERROR | READY | PENDING_ACCEPTANCE | REJECTING | REJECTED` 

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

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

 ** InternalServerError **   
Your request is valid, but Network Firewall couldn't perform the operation because of a system problem. Retry your request.   
HTTP Status Code: 500

 ** InvalidRequestException **   
The operation failed because of a problem with your request. Examples include:   
+ You specified an unsupported parameter name or value.
+ You tried to update a property with a value that isn't among the available types.
+ Your request references an ARN that is malformed, or corresponds to a resource that isn't valid in the context of the request.
HTTP Status Code: 400

 ** ResourceNotFoundException **   
Unable to locate a resource using the parameters that you provided.  
HTTP Status Code: 400

 ** ThrottlingException **   
Unable to process the request due to throttling limitations.  
HTTP Status Code: 400

## See Also
<a name="API_RejectNetworkFirewallTransitGatewayAttachment_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/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for .NET V4](https://docs.aws.amazon.com/goto/DotNetSDKV4/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for C\$1\$1](https://docs.aws.amazon.com/goto/SdkForCpp/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for Go v2](https://docs.aws.amazon.com/goto/SdkForGoV2/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for Java V2](https://docs.aws.amazon.com/goto/SdkForJavaV2/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for JavaScript V3](https://docs.aws.amazon.com/goto/SdkForJavaScriptV3/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for Kotlin](https://docs.aws.amazon.com/goto/SdkForKotlin/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for PHP V3](https://docs.aws.amazon.com/goto/SdkForPHPV3/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for Python](https://docs.aws.amazon.com/goto/boto3/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment) 
+  [AWS SDK for Ruby V3](https://docs.aws.amazon.com/goto/SdkForRubyV3/network-firewall-2020-11-12/RejectNetworkFirewallTransitGatewayAttachment)